Please help me on this!

A student attempts a 10-question multiple-choice test where each question presents four options, and the student makes random guesses for each answer. So the probability of (a) P(5)= 0.058 and (b) P(More than 3)= 0.093.

Part 1: Calculation of probability of getting 5 questions correct

(a) P(5)The formula used to find the probability of getting a certain number of questions correct is:

P(k) = (nCk)pk(q(n−k))

Where, n = total number of questions

(10)k = number of questions that are answered correctly

p = probability of getting any question right = 1/4

q = probability of getting any question wrong = 3/4

P(5) = P(k = 5) = (10C5)(1/4)5(3/4)5= 252 × 0.0009765625 × 0.2373046875≈ 0.058

Part 2: Calculation of probability of getting more than 3 questions correct

(b) P(More than 3) = P(k > 3) = P(k = 4) + P(k = 5) + P(k = 6) + P(k = 7) + P(k = 8) + P(k = 9) + P(k = 10)

P(k = 4) = [tex]10\choose4[/tex](1/4)4(3/4)6 = 210 × 0.00390625 × 0.31640625 ≈ 0.02

P(k = 5) = [tex]10\choose5[/tex](1/4)5(3/4)5 = 252 × 0.0009765625 × 0.2373046875 ≈ 0.058

P(k = 6) = [tex]10\choose6[/tex](1/4)6(3/4)4 = 210 × 0.0002441406 × 0.31640625 ≈ 0.012

P(k = 7) = [tex]10\choose7[/tex](1/4)7(3/4)3 = 120 × 0.00006103516 × 0.421875 ≈ 0.002

P(k = 8) = [tex]10\choose8[/tex](1/4)8(3/4)2 = 45 × 0.00001525878 × 0.5625 ≈ 0.001

P(k = 9) = [tex]10\choose9[/tex](1/4)9(3/4)1 = 10 × 0.000003814697 × 0.75 ≈ 0.000

P(k = 10) = [tex]10\choose10[/tex](1/4)10(3/4)0 = 1 × 0.0000009536743 × 1 ≈ 0

P(More than 3) = 0.020 + 0.058 + 0.012 + 0.002 + 0.001 + 0.000 + 0≈ 0.093

Therefore, the probabilities of the given situations are: P(5) ≈ 0.058, P(More than 3) ≈ 0.093.

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Answer:

Step-by-step explanation:

Choose three values for

x and substitute in to find the corresponding y values.(0,−3),(1,0),(2,3)

You can choose any of these three pairs or the equation y=3x-3

Answer:

y = 12x - 125

Step-by-step explanation:

the equation of a line in slope- intercept form is

y = mx + c ( m is the slope and c the y- intercept )

y = 12x + 3 ← is in slope- intercept form

with slope m = 12

• Parallel lines have equal slopes , then

y = 12x + c ← is the partial equation

to fond c substitute (10, - 5 ) into the partial equation

- 5 = 12(10) + c = 120 + c ( subtract 120 from both sides )

- 125 = c

y = 12x - 125 ← equation of parallel line

Answer:

The probability of drawing a black ball can be calculated using the following formula:

Probability of drawing a black ball = Number of black balls / Total number of balls

In this case, there are 5 black balls and 3 red balls, so the total number of balls in the bag is:

Total number of balls = 5 + 3 = 8

Therefore, the probability of drawing a black ball is:

Probability of drawing a black ball = 5/8

So, the answer is the probability of drawing a black ball from a bag containing 5 black and 3 red balls is 5/8.

Step-by-step explanation:

If an Estate dealer sells houses and makes a commission of GHc3750 for the first house sold and receives GHc500 increase in commission for each additional house sold, for reaching a total commission of GHc6500, she must have sold 6.5 houses.

The number of houses the estate dealer sold to reach a total commission of GHc6500 can be determined using the mathematical operations of subtraction, division, and addition.

The total commission received = GHc6,500

The commission for the first house = GHc3,750

The commission for the remaining houses sold = GHc2,750 (GHc6,500 - GHc3,750)

The commission for additional sale of each house = GHc500

The number of additional houses sold = 5.5 (GHc2,750/GHc500)

The total number of houses sold = 6.5 (5.5 + 1 or the first house)

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The probability of randomly selecting a doctor who is either a General Practitioner or under the age of 40 from a small hospital is 9/19, given 6 out of 19 are General Practitioners, 5 out of 19 are under 40, and 2 are both.

To find the probability of randomly selecting a doctor who is either a General Practitioner or under the age of 40, we need to add the probabilities of these two events and subtract the probability of selecting a doctor who is both a General Practitioner and under the age of 40, since we don't want to count that case twice:

P(General Practitioner or under 40) = P(General Practitioner) + P(Under 40) - P(General Practitioner and under 40)

we know 6 out of 19 doctors are General Practitioners, 5 out of 19 doctors are under the age of 40, 2 doctors are both General Practitioners and under the age of 40.

Therefore:

P(General Practitioner) = 6/19

P(Under 40) = 5/19

P(General Practitioner and under 40) = 2/19

Substituting these values into the formula:

P(General Practitioner or under 40) = 6/19 + 5/19 - 2/19

= 9/19

Therefore, the probability of randomly selecting a doctor who is either a General Practitioner or under the age of 40 is 9/19.

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Answer:

y = -3(x - 2)^2 + 1. Explanation: x-coordinate of vertex: x = -b/(2a) = -12/-6 = 2 y-coordintae of vertex: y(2) = -12 + 24 - 11 = 1

Step-by-step explanation:

Answer:x-coordinate of vertex:

x = -b/(2a) = -12/-6 = 2

y-coordinate of vertex:

y(2) = -12 + 24 - 11 = 1

Vertex form:

y = -3(x - 2)^2 + 1

Check.

Develop y to get back to standard form:

y = -3(x^2 - 4x + 4) + 1 = -3x^2 + 12x - 11.

Step-by-step explanation:

Answer:

2 9/14

Step-by-step explanation:

Given a normal distribution is observed from the number of points per game for a certain basketball player. The mean for this distribution is 20 points and the standard deviation is 3 points.Using the empirical rule for normal distributions, the probability that in a randomly selected game the player scored less than 26 points is required .Empirical Rule: For a normal distribution with a mean µ and a standard deviation σ, the probability of an observation being within k standard deviations of the mean is approximately:•

68% of the observations fall within one standard deviation of the mean.• 95% of the observations fall within two standard deviations of the mean.• 99.7% of the observations fall within three standard deviations of the mean.Here, the mean is 20 points and the standard deviation is 3 points. We need to find the probability of getting less than 26 points.z-score = (x - µ) / σ = (26 - 20) / 3 = 2σ = 2According to the empirical rule, 95% of observations fall within 2 standard deviations of the mean.So, the probability that the player scored less than 26 points is 95%.Therefore, the final answer is 95% rounded to one decimal place. Answer: 95%.

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The radius of the cylinder is r = 13 cm

The radius of a cylinder is the radius of the circular base of the cylinder.

Since the volume of a cylinder is 15, 919.8 cm³. If the height is 30 cm, we require it radius.

Using the formula for volume of a cylinder V = πr²h where

Making r subject of the formula, we have that

r = √V/πh

Since

Substituting the values of the variables into the equation for the radius, we have that

r = √V/πh

r = √(15,919.8 cm³/[3.142 × 30 cm])

r = √(15,919.8 cm³/94.26 cm)

r = √168.8924 cm²

r = 12.995 cm

r ≅ 13 cm

So, the radius r = 13 cm

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Answer:

y=-17

Step-by-step explanation:

1-2(9)=1-18=-17

Answer: y = -17

Step-by-step explanation:

Using PEMDAS, you need to do the multiplication first. 2 times x is 18, because the value of x is 9. You will then get 1 - 18. This is -17, so y = -17. I hope that this helped! :)

Answer:

d(0) = -3

Step-by-step explanation:

d(x) = -x + -3                           d(0)

d(0) = 0 - 3

d(0) = -3

So, the answer is d(0) = -3

Answer:

Step-by-step explanation:

It is set up

7x+5x+2y=20

7x+5x=12x

12x+2y=20

x=0

y=10

12(0)+2(10)=20

Ok so maybe this was not the same type of equation i thought it was it is not that easy!

Answer:

1034 x 10⁷

Step-by-step explanation:

the seven just means to multiply by 10 seven times

Let me know if this helps.

Answer: -17x+3

Step-by-step explanation:

y=2x+3 and y=15-x

15x-2x+3

-17x+3

you can try this

The lower limit of a 90% confidence interval for the average difference in the number of days the temperature was above 90 degrees between 1948 and 2018 is -22.8 days and the upper limit is 28.6 days.

The margin of error for the 90% confidence interval is 25.4 days.

The 90% confidence interval does provide evidence that the number of 90-degree days increased globally comparing 1948 to 2018.

The 99% confidence interval also provides evidence that the number of 90-degree days increased globally comparing 1948 to 2018.

If the mean difference and standard deviation stay relatively constant, decreasing the degrees of freedom would make it harder to conclude that there are more days above 90 degrees in 2018 versus 1948 globally.

Lowering the confidence level would also make it harder to conclude that there are more days above 90 degrees in 2018 versus 1948 globally.

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In monopolistic competition, the end result of entry and exit is that firms end up with a price that lies on the downward-sloping portion of the average cost curve.

Monopolistic competition is a market condition in which many small firms compete with each other by selling slightly varied, but essentially comparable goods or services at somewhat different prices. These companies enjoy some market power, but they are not monopolies because their products or services are close substitutes for each other.

The equilibrium price in a monopolistically competitive market is a long-run, but not a short-run, outcome of entry and exit. Because the market is monopolistic, entry and exit do not have an immediate impact on the price; it simply alters the number of producers operating in the market. Over time, the entry and exit of producers in the industry will increase or decrease the number of substitutes available, driving demand curves and resulting in the price of the commodity settling on the down-sloping portion of the average cost curve in the long run.

Therefore, it can be concluded that the end result of entry and exit in monopolistic competition is that companies end up with a price that lies on the downward-sloping portion of the average cost curve.

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Answer:

136

Step-by-step explanation:

35x2+7x6+12x2

The probability of all will fail is the lowest.

The given problem states that a missile guidance system has seven fail-safe components, and the probability of each failing is 0.2. The given variable is binomial. We need to find the following probabilities:

(a) Exactly two will fail.

(b) More than two will fail.

(c) All will fail.

(d) Compare the answers for parts a, b, and c, and explain why these results are reasonable.

(a) Exactly two will fail.

The probability of exactly two will fail is given by;

P(exactly two will fail) = (7C2) × (0.2)2 × (0.8)5
= 21 × 0.04 × 0.32768
= 0.2713

Therefore, the probability of exactly two will fail is 0.2713.

(b) More than two will fail.

The probability of more than two will fail is given by;

P(more than two will fail) = P(X > 2)
= 1 - P(X ≤ 2)
= 1 - (P(X = 0) + P(X = 1) + P(X = 2))
= 1 - [(7C0) × (0.2)0 × (0.8)7 + (7C1) × (0.2)1 × (0.8)6 + (7C2) × (0.2)2 × (0.8)5]
= 1 - (0.8)7 × [1 + 7 × 0.2 + 21 × (0.2)2]
= 1 - 0.2097152 × 3.848
= 0.1967

Therefore, the probability of more than two will fail is 0.1967.

(c) All will fail.

The probability of all will fail is given by;

P(all will fail) = P(X = 7) = (7C7) × (0.2)7 × (0.8)0
= 0.00002

Therefore, the probability of all will fail is 0.00002.

(d) Compare the answers for parts a, b, and c, and explain why these results are reasonable.

The probability of exactly two will fail is the highest probability, followed by the probability of more than two will fail. And, the probability of all will fail is the lowest probability. These results are reasonable since the more the number of components that fail, the less likely it is to happen. Therefore, it is reasonable that the probability of exactly two will fail is higher than the probability of more than two will fail, and the probability of all will fail is the lowest.

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Answer: Differential Equation Initial Condition y' + y tan x = sec X + 9 cos x y(0) ... linear differential equation for x > 0 that satisfies the initial condition.

Step-by-step explanation:

Answer:

1,880 sq in ÷ 600 sq in/can ≈ 3.13 cans

If you want you can round that to 4 cans.

The following is the recursive formula for the arithmetic sequence in this issue:

c(1) = -16.

c(n) = c(n - 1) - 17.

An arithmetic sequence is a series of numbers where each term is obtained by adding a fixed constant, known as the common difference, to the previous term. For example, in the sequence 2, 5, 8, 11, 14, 17, each term is obtained by adding 3 to the previous term.

The formula for finding the nth term of an arithmetic sequence is: a(n) = a(1) + (n-1)d, where a(1) is the first term, d is the common difference, and n is the term number. For example, to find the 10th term of the sequence 2, 5, 8, 11, 14, 17, we would use the formula a(10) = 2 + (10-1)3 = 29. Arithmetic sequences have many practical applications, such as in finance, where they can be used to calculate the interest earned on an investment over time.

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Answer: The two angles are 117 degrees and 63 degrees.

Step-by-step explanation:

Supplementary angles are two angles whose sum is 180 degrees. Let the two angles be 13x and 7x, where x is a constant of proportionality.

We know that the sum of the angles is 180 degrees, so:

13x + 7x = 180

Combining like terms, we get:

20x = 180

Dividing both sides by 20, we get:

x = 9

So the measures of the angles are:

13x = 13(9) = 117 degrees

7x = 7(9) = 63 degrees

Therefore, the two angles are 117 degrees and 63 degrees.

If y is directly proportional to x, when x = 60, y = 6.

Proportional refers to a relationship between two quantities in which one quantity is a constant multiple of the other. In other words, if one quantity increases or decreases by a certain factor, the other quantity will also increase or decrease by the same factor.

Directly proportional is a specific type of proportionality where two quantities increase or decrease by the same factor. In other words, if one quantity doubles, the other quantity also doubles. If one quantity triples, the other quantity also triples, and so on.

In the given question,

If y is directly proportional to x, we can use the formula:

y = kx

where k is the constant of proportionality.

To find the value of k, we can use the given values:

y = kx

50 = k(500)

Solving for k:

k = 50/500

k = 0.1

Now that we know the value of k, we can use the formula to find the value of y when x = 60:

y = kxy = 0.1(60)

y = 6

Therefore, when x = 60, y = 6.

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The Riemann sum is:Σ(3-xᵢₖ*yᵢₖ²)ΔA, where i=1,2 and k=1,2,3.

We can create a Riemann sum to estimate the value of the double integral ∬R (3-xy²) dA over the rectangular region R=[0, 4]×[-1, 2] by subdividing [0, 4] into m=2 intervals and [-1, 2] into n=3 intervals. Then we can evaluate the function at the upper left corner of each subrectangle, multiply by the area of the rectangle, and sum all the results.

The width of each subinterval in the x-direction is Δx=(4-0)/2=2, and the width of each subinterval in the y-direction is Δy=(2-(-1))/3=1. The area of each subrectangle is ΔA=ΔxΔy=2*1=2.

Therefore, the Riemann sum is:

Σ(3-xᵢₖ*yᵢₖ²)ΔA, where i=1,2 and k=1,2,3.

Evaluating the function at the upper left corner of each subrectangle, we get:

(3-0*(-1)²)2 + (3-20²)2 + (3-21²)2 + (3-41²)*2 = 2 + 6 + 2 + (-22) = -12.

Thus, the estimate for the double integral is -12.

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Answer:

-4

Step-by-step explanation:

substitute -2 into the formula and solve

[tex]f(x)=(-2)^2+3(-2)-2\\f(x)=4+(-6)-2\\\boxed{f(x)=-4}[/tex]

Answer:

(x-7)(x+6)

factor and see what works