Find the volume of the figure below.
D
- 12 m

Approximately 95.44% of the data falls within ±2 standard deviations of the mean in a normal distribution.

To find the percentage of the area under the normal curve that falls between ±2 standard deviations, we need to follow the following steps:

We need to know the mean (μ) and standard deviation (σ) of the normal distribution in question. If we assume a standard normal distribution (i.e., a normal distribution with mean of 0 and standard deviation of 1), then we can use a z-score table to find the percentage of area under the curve.

The z-score formula is:

z = (x - μ) / σ

For ±2 standard deviations, the values of x are μ ± 2σ. Therefore, the z-scores are:

z = (μ + 2σ - μ) / σ = 2

z = (μ - 2σ - μ) / σ = -2

A z-score table gives the percentage of area under the standard normal curve that falls to the left of a given z-score. Since the normal distribution is symmetric, the percentage of area to the right of a negative z-score is the same as the percentage of area to the left of the corresponding positive z-score.

Using a z-score table, we find that the percentage of area under the standard normal curve that falls to the left of z = 2 is 0.9772, or 97.72%. Therefore, the percentage of area under the curve that falls between ±2 standard deviations is:

97.72% - (100% - 97.72%) = 95.44%

This means that approximately 95.44% of the data falls within ±2 standard deviations of the mean in a normal distribution.

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The expression for the number of non-adult sizes is s - 19.

A value or amount is represented by an expression, which is a collection of numbers, variables, and mathematical operations like addition, subtraction, multiplication, and division. Calculations, complicated mathematical equations, and issues in a variety of disciplines, including science, engineering, economics, and statistics, may all be solved using expressions. Functions that depict a connection between variables, such as sin(x) and log(x), can also be included in expressions. Expressions are frequently employed to simulate real-world circumstances and provide predictions based on mathematical analysis.

Given that the total number od sweatshirts = s.

The number of non-adult sweatshirts can be calculated by:

Number of non-adult sizes = Total number of sweatshirts sold - Number of adult sizes

= s - 19

Hence, the expression for the number of non-adult sizes is s - 19.

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The player should be willing to pay up to $1.33 to play this game and not lose money in the long run.

The expected value is the sum of the products of each possible outcome and its probability. Let's calculate the expected value of the game:

E(X) = (1/6) * $4 + (5/6) * (-$2)

E(X) = $0.67

This means that on average, the player can expect to win $0.67 per game. Since it costs $2 to play, the player should not be willing to pay more than $2 - $0.67 = $1.33 to play the game and not lose money in the long run.

Probability theory is based on axioms, which are basic assumptions about the nature of probability. It is used to quantify uncertainty and to make predictions based on the available information. Probability is expressed as a number between 0 and 1, with 0 meaning an event is impossible, and 1 meaning an event is certain.

The concept of probability is used in a variety of fields, including statistics, economics, engineering, and physics. In statistics, probability is used to model random variables, estimate parameters, and test hypotheses. In economics, probability is used to model financial risks and decision-making under uncertainty. In engineering and physics, probability is used to model complex systems and predict the behavior of particles.

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Answer:

Step-by-step explanation:

2(-4) - 3(-2) = -2

 -8 + 6 = -2

   -2 = -2

a. Finding the transition matrix from B1 to B2 using the standard basis for the vector space of lower triangular matrices with zero trace.The standard basis of the vector space of lower triangular matrices with zero trace is given by{(1,0,0),(0,1,0),(0,0,0)}.We are to find the transition matrix from B1 to B2. We start with the definition of the transition matrix. This definition states that if A = [a1,a2,a3] is a matrix whose columns are the vectors of B2, then the transition matrix from B1 to B2 is the matrix S such that S = [b1,b2,b3] where bi is the column vector obtained by expressing the ith vector of B1 as a linear combination of the vectors of B2. Using the standard basis, we have that (1,0,0) = a1, (0,1,0) = a2 and (0,0,0) = a3. Therefore, we need to express each of these standard basis vectors as a linear combination of the vectors of B1.For (1,0,0), we have(1,0,0) = 2e1 - e2For (0,1,0), we have(0,1,0) = -3e1 + e3For (0,0,0), we have(0,0,0) = e2 + e3Therefore, the transition matrix S is given by S = [b1,b2,b3] where bi is obtained by expressing the ith vector of the standard basis as a linear combination of the vectors of B1. Thus,S = [(2,-3,0),(-1,1,0),(0,0,1)]b. Finding the coordinates of v in B if the coordinate vector of v in B1 is c. Let c be the coordinate vector of v with respect to B1. Then we know that v = c1e1 + c2e2 + c3e3. We are to find the coordinate vector of v with respect to B.We know that B is a basis for the vector space of lower triangular matrices with zero trace, so any vector in this space can be expressed uniquely as a linear combination of the vectors in B. Thus, we can write v as a linear combination of the vectors of B.v = a1x1 + a2x2 + a3x3We are to find the coefficients x1, x2 and x3. We do this by using the fact that the transition matrix S from B1 to B is such that v = Sc where c is the coordinate vector of v with respect to B1. Hence, v = Sc = [b1,b2,b3][c1,c2,c3] = (2c1 - c2) b1 - (c1 - c2) b2 + c3 b3Using the expressions for b1, b2 and b3 in terms of the standard basis vectors, we obtainv = (2c1 - c2)(2e1 - e2) - (c1 - c2)(-e1 + e3) + c3e3

Expanding this expression and comparing coefficients with the equation for v above yields(2c1 - c2)(2e1 - e2) - (c1 - c2)(-e1 + e3) + c3e3 = c1e1 + c2e2 + c3e3Therefore, we have the system of equations2(2c1 - c2) - (c1 - c2) = c11(2c1 - c2) + (c1 - c2) = c20 = c3Solving for x1, x2 and x3 yieldsx1 = c2/2, x2 = c1/2, and x3 = 0Therefore, the coordinate vector of v with respect to B is given by the vector( c2/2, c1/2, 0).c. Finding [v]B2 in 200 wordsWe are to find the coordinate vector of v with respect to B2. Since we already have the coordinate vector of v with respect to B1, we can use the transition matrix S from B1 to B2 to obtain this coordinate vector.Let c be the coordinate vector of v with respect to B1. Then, we know that v = c1e1 + c2e2 + c3e3. Since the coordinate vector of v with respect to B1 is c, we have the equationc = [c1,c2,c3]Using the transition matrix S from B1 to B2, we can write the coordinate vector of v with respect to B2 as[x1,x2,x3] = S[c1,c2,c3]Multiplying these matrices together yields the equation[x1,x2,x3] = [(2,-3,0),(-1,1,0),(0,0,1)][c1,c2,c3]

Expanding this equation gives the system of equations2c1 - c2 = x1-3c1 + c2 = x2c3 = x3Solving this system of equations for c1, c2 and c3 yieldsc1 = (x2 - x1)/4, c2 = (3x2 + x1)/4, and c3 = x3Therefore, the coordinate vector of v with respect to B2 is given by the vector((x2 - x1)/4, (3x2 + x1)/4, x3).

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The mean of time between success is 0.2 minutes, rate parameter is 5 and probability that the time to succeed will be more than 55 minutes is approximately 0.000026 when Poisson random variable has a mean of 5 successes over a 125-minute period.

They can be found out by:

(A) The mean of the random variable defined by the time between successes can be found by using the fact that the Poisson distribution is memory less, which means that the time between successes follows an exponential distribution. The mean of an exponential distribution is equal to the reciprocal of the rate parameter, so:

 Mean of time between successes = 1 / rate parameter = 1 / 5 = 0.2 minutes

(B) The rate parameter of the exponential distribution can be found using the fact that the mean of the exponential distribution is equal to the reciprocal of the rate parameter, as derived in part a:

 rate parameter = 1 / mean of time between successes = 1 / 0.2 = 5

(C)The probability that the time to success will be more than 55 minutes can be found using the cumulative distribution function (CDF) of the exponential distribution with the rate parameter found in part b:

P(X > 55) = 1 - P(X <= 55) = 1 - F(55) = 1 - (1 - e^{(-5*55)}) = 0.000026 (rounded to 4 decimal places)

Therefore, the probability that the time to success will be more than 55 minutes is very small, approximately 0.000026.

The mean of random variable defined by time between success is 0.2 minutes, rate parameter of exponential distribution is 5 and probability that the time to succeed will be more than 55 minutes is approximately 0.000026 .

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Check the picture below.

Answer:

x=-3

Step-by-step explanation:

Answer: 24

Step-by-step explanation:

Surface Area of a rectangular prism = 2 (lh +wh + lw ) Square units.

                                                              = 2[(2*2)+(2*2)+(2*2)]

                                                               = 2[4+4+4]

                                                                =2[12]

                                                                  24

Measure of last angle of triangle is 117°

The triangle's characteristics include:

The angle sum property states that the sum of a triangle's three interior angles is always 180 degrees.

Angle of Triangle are

28° and 35°

Let the third angle be x

According to angle sum property

28°+35°+x=180°

x=117°

Measure of last angle of triangle is 117°

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The complete question is;

Find the measure of the last angle of the triangle below.

28⁰

35°

Image is attached below.

Explanation:

Use the pythagorean trig identity to determine sine based on cos(theta) = 0.6

[tex]\sin^2(\theta)+\cos^2(\theta) = 1\\\\\sin^2(\theta)=1-\cos^2(\theta)\\\\\sin(\theta)=\pm\sqrt{1-\cos^2(\theta)}\\\\\sin(\theta)=-\sqrt{1-\cos^2(\theta)} \ \ \text{....sine is negative in quadrant Q4}\\\\\sin(\theta)=-\sqrt{1-(0.6)^2}\\\\\sin(\theta)=-\sqrt{1-0.36}\\\\\sin(\theta)=-\sqrt{0.64}\\\\\sin(\theta)=-0.8\\\\[/tex]

Since [tex]\cos(\theta)=0.6 \text{ and } \sin(\theta)=-0.8[/tex], the location of point P is (0.6, -0.8)

Recall that for any point (x,y) on the unit circle, we have:

[tex]\text{x}=\cos(\theta)\\\\\text{y}=\sin(\theta)[/tex]

meaning cosine is listed first in any (x,y) pairing.

Answer:

90 degrees then decreace that then turn that into a fraction

Step-by-step explanation:

Answer: 105

Step-by-step explanation:

OBTUSE ANGLE (105°) IS FORMED AT 2:30 IN THE CLØCK.

As we know 12 division OF 360° CIRCLE GIVES 30°

AT TWO PM THE ANGLE BETWEEN HOUR AND MINUTE HAND IS 60° AFTER 30 MIN ARM ROTATES 180° AND HOUR ARM 30°/2 = 15°

SO THE ANGLE BETWEEN TWO ARMS IS (180-(60-15)

105

By using the Lagrange multipliers, the two points on the cone that is closest to (14, 8, 0) are:

(7, 4, √65) and (7, 4, -√65)

We want to minimize the distance between the point (14, 8, 0) and the points on the cone z^2 = x^2 + y^2. The distance squared between two points (x_1, y_1, z_1) and (x_2, y_2, z_2) is given by:

d^2 = (x2 - x1)^2 + (y2 - y1)^2 + (z2 - z1)^2

In our case, we want to minimize the distance squared between (14, 8, 0) and a point (x, y, z) on the cone z^2 = x^2 + y^2:

d^2 = (x - 14)^2 + (y - 8)^2 + z^2

Subject to the constraint z^2 = x^2 + y^2. We can use Lagrange multipliers to solve this constrained optimization problem. Let L be the Lagrangian:

L = (x - 14)^2 + (y - 8)^2 + z^2 - λ(z^2 - x^2 - y^2)

Taking the partial derivatives of L with respect to x, y, z, and λ, and setting them to zero, we get:

2(x - 14) - 2λx = 0.....(1)

2(y - 8) - 2λy = 0.....(2)

2z - 2λz = 0.....(3)

z^2 - x^2 - y^2 = 0.....(4)

Simplifying the third equation, we get z(1 - λ) = 0. Since we want to find points where z is not zero, we must have λ = 1. Then, from the first two equations, we get x = 7 and y = 4. Substituting these values into the fourth equation, we get:

z^2 = x^2 + y^2 = 65

So the two points on the cone that is closest to (14, 8, 0) by using  Lagrange multipliers are:

(7, 4, √65) and (7, 4, -√65)

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Answer: Xavier will receive $3.21 in change.

Step-by-step explanation:

To find the change Xavier receives, we need to subtract the cost of the dog collar from the amount he paid with his $10 bill:

Change = $10 - $6.79 = $3.21

Therefore, Xavier will receive $3.21 in change.

Answer: 9/6 or 1 1/2

Step-by-step explanation:

9/2 ÷ 3

KCF (keep, change, flip)

9/2 × 1/3

Solve.

Final answer: 9/6

hope i helped :)

Answer:

The associated growth factor for a 30% increase is 1 + 0.30 = 1.30.

The associated growth factor for a 30% decrease is 1 - 0.30 = 0.70.

The associated growth factor for a 2% increase is 1 + 0.02 = 1.02.

The associated growth factor for a 2% decrease is 1 - 0.02 = 0.98.

The associated growth factor for a 0.04% increase is 1 + 0.0004 = 1.0004.

The associated growth factor for a 0.04% decrease is 1 - 0.0004 = 0.9996.

The associated growth factor for a 100% increase is 1 + 1 = 2.

Step-by-step explanation:

A growth factor is a multiplier that represents the amount by which a quantity changes as a result of a growth rate or percentage change. It is calculated by adding 1 to the decimal form of the growth rate. For example, if the growth rate is 30%, the decimal form is 0.30, and the growth factor is 1 + 0.30 = 1.30.

In case of a decrease, the growth factor is calculated by subtracting the decimal form of the decrease rate from 1. For example, if the decrease rate is 30%, the decimal form is 0.30, and the growth factor is 1 - 0.30 = 0.70.

In cases where the growth rate is a small percentage, it is important to convert it into a decimal by dividing the percentage by 100 before calculating the growth factor.

In the case of a 100% increase, the quantity doubles, so the growth factor is 2 (i.e., 1 + 1).

The smallest number of beads we can take so that the conditions for performing inference are met is 40.

Probability:

The probability of an event is a number that indicates the probability of the event occurring. Expressed as a number between 0 and 1 or as a percent sign between 0% and 100%. The more likely an event is to occur, the greater its probability. The probability of an impossible event is 0; the probability of a certain event occurring is 1. The probability of two complementary events A and B - A occurring or B occurring - adds up to 1.

According to the Question:

Given in the question,

Teacher prepares a large container filled with colored beads. She claims that 1/8 beads are red, 1/4are blue, and the rest are yellow. Your class will test the teacher's claim by randomly drawing a simple sample of beads from the container.

Quadrant                     Frequency

      1                                    18

      2                                   22

      3                                   39

      4                                   21

The proportions are 1/8 , 1/4 and 5/8

Here, the smallest probability is 1/8 , thus it would be used to compute the frequency.

Now,

The expected frequencies are calculated as:

E = np₁ = 15 (1/8) = 1.875

E = np₂ = 16(1/8) = 2

E = np₃ = 30(1/8) = 3.75

E = np₄ = 40(1/8) = 5

E = np₅ = 80(1/8) = 10

Here, conditions are fulfilling for 40 and 90 but the smallest sample size is contained by 40. Thus, the correct option is 40.

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Tomas can spend at most $118.50 each day. The inequality equation is 5.5x ≤ 651.75.

Tomas has $1,000 to spend on a vacation. His plane ticket costs $348.25. If he stays 5.5 days at his destination, how much can he spend each day? Write an inequality and then solve.

Let x be the amount that Tomas can spend each day. Since Tomas has to pay for the plane ticket, he will have $1,000 − $348.25 = $651.75 left to spend on the rest of the vacation.

Then, since he is staying for 5.5 days, the total amount he can spend would be 5.5x dollars. The inequality that represents the problem is as follows:

5.5x ≤ 651.75

To solve for x, divide both sides by 5.5

5.5x/5.5 ≤ 651.75/5.5x ≤ 118.5

Therefore, Tomas can spend at most $118.50 each day.

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Answer:

The answer to this solution is 118.5 a day

Step-by-step explanation:

The original price is $1,000 for the ticket it costs $348.25 and Tomas is staying for 5.5 days so dividing 651.75 by 5.5 is the ANSWER 118.5

Answer:

[tex]735 = 3 \times 5 \times {7}^{2} [/tex]

Step-by-step explanation:

[tex]735 = 7 \times 105[/tex]

[tex]735 = 7 \times 3 \times 35[/tex]

[tex]735 = 7 \times 3 \times 5 \times 7[/tex]

[tex]735 = 3 \times 5 \times {7}^{2} [/tex]

Two teaspoons of salt contains 7.16 grams of Na or 7160 milligrams of Na.

Given that a soup recipe calls for two teaspoons of salt. We need to find out how many milligrams of sodium is that?

1 teaspoon = 5.69 grams      1 gram = 1000 milligrams

2 teaspoons of salt = 2 * 5.69 grams = 11.38 grams of salt

11.38 grams of salt = 11.38 * 1000 milligrams = 11380 milligrams of salt

Now, we have to find out how much sodium (Na) is there in 11380 milligrams of salt. Sodium chloride is the chemical name for table salt (NaCl). So, the atomic mass of NaCl can be calculated as follows:

Na = 1Cl = 35.45

Atomic mass of NaCl = Na + Cl= 1 + 35.45= 36.45

So, 1 mole of NaCl = 36.45 grams         11380 milligrams of NaCl = 11380/1000 grams= 11.38/36.45 moles

Therefore, Moles of Na = 11.38/36.45 = 0.3121

mol Atomic mass of Na is 22.99 g/mol.

So, 1 mole of Na weighs = 0.3121 * 22.99= 7.16 grams

Therefore, 11380 milligrams of NaCl = 7.16 grams of Na. Hence, two teaspoons of salt contains 7.16 grams of Na or 7160 milligrams of Na.

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Answer:

8×21=168? That would make it 168=168? Or you could multiply even more to make 8×25 or somethin?

Step-by-step explanation: I don't know what answer ur looking for but there's some help

Answer:

x < 21.

Step-by-step explanation:

Given the equation: 8x < 168, solve the inequality.

First, make it as if it was an equality and solve x:

8x = 168  (Divide both sides by 8)

x = 21

That means x < 21.

To place two bench press machines in a small area, you will need a space of approximately 10 feet by 10 feet. Let's discuss it in detail below. Here are the dimensions of the bench press machine, which can help determine the amount of space required to fit two bench press machines in a small area:

The length of the bench press machine is between 48 inches and 54 inches.

The width of the bench press machine is between 28 inches and 32 inches.

The height of the bench press machine is between 48 inches and 56 inches.

Based on the above dimensions of the bench press machine, two machines can be placed in a small area of 10 feet by 10 feet. However, for safe use, the following guidelines should be followed:

There should be at least 6 feet of distance between the two bench press machines. There should be at least 3 feet of clearance in the front of the bench press machine to allow for safe movement during exercises. There should be at least 2 feet of clearance behind the bench press machine to allow for a safe exit in case of an emergency.

Thus, to place two bench press machines in a small area, you will need a space of approximately 10 feet by 10 feet.

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Answer:

-9

Step-by-step explanation:

x = -5

3x + 6

Since x = -5..

Do this

3(-5) + 6

Perform

-15 + 6

Answer: -9

Therefore, when x is equal to -5, the value of 3x + 6 is -9.

An equation is a statement that expresses the equality of two mathematical expressions using mathematical symbols such as variables, numbers, and mathematical operations. The equality is represented by an equal sign "=" between the two expressions. Equations are used to represent mathematical relationships and solve problems in various fields such as physics, chemistry, engineering, and economics.

Given by the question.

3x + 6 = 3(-5) + 6

= -15 + 6

= -9

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the given side that measures 2 1/4 inches with the corresponding length measurement. Label the angle between these sides as 60°.

A triangle is a polygon with three sides, three vertices, and three angles. The sum of the interior angles of a triangle is always 180 degrees, and the longest side of a triangle is opposite to the largest angle, and the shortest side is opposite to the smallest angle. Triangles can be classified according to their side lengths and angles. For example, an equilateral triangle has three equal sides and three equal angles of 60 degrees each, while an isosceles triangle has two equal sides and two equal angles. A scalene triangle has no equal sides or angles. Triangles are important in geometry and have many applications in mathematics and other fields, such as architecture, engineering, physics, and computer graphics.

by the question.

Draw a straight-line segment and label it as the given side that measures 1 1/2 inches.

From one endpoint of the first line segment, draw another line segment that forms a 60° angle with the first line segment. Label this second line segment as the given side that measures 2 1/4 inches.

Draw a third line segment that connects the endpoints of the first two-line segments. This will complete the triangle.

To label the triangle, label the given side that measures 1 1/2 inches with the corresponding length measurement, and label the given side that measures 2 1/4 inches with the corresponding length measurement. Label the angle between these sides as 60°.

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The given series in the sigma notation can be written as [tex]\sum_{n = 1} ^ 5 10n - 8[/tex].

An arithmetic series is a set of integers where each term is made up of the common difference, a fixed amount, and the sum of the terms before it. In other words, the terms of the series may be represented as follows if the first term of an arithmetic series is a and the common difference is d:

a, a + d, a + 2d, a + 3d, ...

The given series is 2 + 12 + 22 + 32 + 42.

The total number of terms are 5.

The first term is 2, and the common difference is:

d = 12 - 2 = 10

Now, using the nth term of sequence we have:

an = 2 + (n - 1) 10

= 10n - 8

= [tex]\sum_{n = 1} ^ 5 10n - 8[/tex]

Hence, the given series in the sigma notation can be written as [tex]\sum_{n = 1} ^ 5 10n - 8[/tex].

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Answer:

The sequence is defined as follows:

a1 = 5

an = an-1 - 5, for n > 1

Using this definition, we can find the first four terms of the sequence as follows:

a1 = 5

a2 = a1 - 5 = 5 - 5 = 0

a3 = a2 - 5 = 0 - 5 = -5

a4 = a3 - 5 = -5 - 5 = -10

Therefore, the first four terms of the sequence are: 5, 0, -5, -10.

The largest possible whole-number length for the third side is 18, which satisfies all three inequalities.

The triangle inequality theorem explains the relationship between the three sides of a triangle. This theorem states that for any triangle, the sum of the lengths of the first two sides is always larger than the length of the third side.

Let x be the length of the third side. By the triangle inequality, we have:

3 + 16 > x and 16 + x > 3 and 3 + x > 16

Simplifying, we get:

19 > x and x > 13 and x < 19

The largest possible whole-number length for the third side is 18, which satisfies all three inequalities.

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Answer:

Let A represent the cost of purchasing a pool membership from the Aquatics Club and let S represent the cost of purchasing a pool membership from the Swimming Hole. Then, we can write the following system of inequalities:

A ≤ y

A = 75 + 20x

S ≤ y

S = 15 + 65x

The first two inequalities represent the cost of purchasing a membership from the Aquatics Club, while the last two represent the cost of purchasing a membership from the Swimming Hole. The inequalities ensure that the cost of purchasing a membership from either company does not exceed Alfonso's budget of y dollars.

Answer:

Equation: 2(357+30×5) = 580

x=4

Step-by-step explanation:

In one package, there is such a relationship:

357+30X5 = y

(Y is the price of a package)

The price of two parcels is 580:

then. 24=580

y= 290

x=4, so: equation: 2(35x+150) =580

Step-by-step explanation:

A shopkeeper buys a number of books for Rs. 80. If he had bought 4 more for the same amount each book would have cost Rs. 1 less. How many books did he buy?

A

8

B

16

Correct Answer

C

24

D

28

Medium

Open in App

Updated on : 2022-09-05

Solution



Verified by Toppr

Correct option is B)

Let the shopkeeper buy x number of books. 

According to the given condition cost of x books =Rs80

Therefore cost of each book =x80

Again when he had brought 4 more books

Then total books in this case =x+4

So cost of each book in this case =x+480

According to Question, 

x80−x+480=1

x(x+4)80(x+4)−80x=1

x2+20x−16x−320=0

(x−16)(x+20)=0

x=16orx=−20

Hence the shopkeeper brought 16 books