Please Explain step-by-step

An algebra class contains 30 students. Forty
percent of the students in the class are girls. How
many boys are in the class?

Answer:

262 pennies

Step-by-step explanation:

If Layla already has 388 pennies and she needs 600 pennies total, all she needs to do is is take the amount she already has away from 600:

Answer:

Step-by-step explanation:

Convert 182 6/8 into improper fraction

[tex]182\frac{6}{8}=\frac{1462}{8}[/tex]

[tex]\frac{1462}{8}[/tex]÷ 3 =[tex]\frac{1462}{8}*\frac{1}{3}=\frac{1462}{24}[/tex]

= 60 22/24

Answer:

Z - score = 2.83

Step-by-step explanation:

Given the following :

Number of samples (N) = 60

Sample mean (x) = 41.9mg

Population mean (μ) = 40mg

Population standard deviation (sd) = 5.2

Using the relation :

Z = (x - μ) / (sd / √N)

Z = (41.9 - 40) / (5.2 / √60)

Z = 1.9 / (5.2 / 7.7459666)

Z = 1.9 / 0.6713171

Z = 2.8302570

Therefore, the z-score = 2.83

Answer:

centre = (11, 0 ), radius = 3

Step-by-step explanation:

The equation of a circle in standard form is

(x - h)² + (y - h)² = r²

where (h, k) are the coordinates of the centre and r is the radius

Given

(x - 11)² + y² = 9 ← in standard form

with (h, k ) = (11, 0 ) and r² = 9 ⇒ r = [tex]\sqrt{9}[/tex] = 3

centre = (11, 0 ) and r = 3

Answer:

( 0,0) and (3,0)

Step-by-step explanation:

y=(2x(x-3))/(x-1)

Set y = 0

0 =(2x(x-3))/(x-1)

Multiply each side by x-1, which makes x not equal to 1

0 =(2x(x-3))

Using the zero product property

2x=0  x-3 =0

x=0   x= 3

The x intercepts are x=0   x= 3

( 0,0) and (3,0)

Answer: [tex]64.3=\frac{1}{3}(B)(7)[/tex]

Step-by-step explanation:

[tex]V=\frac{1}{3} Bh[/tex]

B is the area of the base

h is the height of the cone

[tex]V=64.3 cm^3[/tex]

[tex]h=7cm[/tex]

[tex]64.3=\frac{1}{3}(B)(7)[/tex]

[tex]192.9=(B)(7)[/tex]

[tex]B=192.9/(7)[/tex]

[tex]=27.56cm^2[/tex]

Answer:

New cost of the shirt=$39.028416

Step-by-step explanation:

Target is having a Back to School sale where all polo shirts are discounted by 20%. Joshua wants to buy five shirts: two cost $10.98 each, one costs $11.50, and two others cost $15.99 each. Joshua remembered he had a coupon in his pocket that would take an additional 30% of the shirts. Which choice represents the new total cost of the shirts including the sales tax of 6.5%

Solution

Two shirts cost=$10.98 each

One shirt cost=$11.50

Two shirts cost=$15.99 each

Total cost of shirts=(2*$10.98 + $11.50 + 2*$15.99)

=$21.96 + $11.50 + $31.98

=$65.44

All polo shirts are discounted by 20%

It means he would pay 100%-20% of the total cost

100%-20%=80%

Discounted price=$65.44 * 80%

=$65.44 * 0.8

=$52.352

He has a coupon of 30% off the shirt

100% -30%=70%

=$52.352*70%

=$52.352 * 0.7

=$36.6464

Plus Sales tax of 6.5%

6.5% of $36.6464

=0.065* $36.6464

=$2.382016

New cost of the shirt=$36.6464 + $2.382016

=$39.028416

Answer:

21 windows

Step-by-step explanation:

collen family plans to paint the windows of their house. her father will paint twice as many windows as her mother, and collen and her 2 brothers will paint an equal number of the rest of the windows. Colleen decided to do her own share and her mother's share and paints 7 window, which is one less than her father's share. how many windows are in their house?

Answer: Let the number of window Collen father would paint be a while that of her mother be b. Since her father will paint twice as many window as her mother, therefore the number of windows painted by the father a = 2b

Let the number of windows that would be needed to be painted each by Colleen and her 2 brothers be c because they would paint the equal number of windows.

The total number of windows to be painted = 2b + b + c + c + c = 3b + 3c = 3(b + c).

Collen painted 7 windows as her mother and her own share which is one less than the fathers share. Therefore b + c = 7.

Also the fathers share a = 2b = 7 + 1 = 8 windows. Therefore b = 4 which is the mother share

Therefore the total number of windows = 3(b + c) = 3(7) = 21 windows

3b + 3c =  21

3(4) + 3c = 21

12 + 3c = 21

3c = 21 - 12

3c = 9

c = 3 which is collen and her brothers share

Answer:

a. 8 gallons

b. (11-0.75t) gallons

Step-by-step explanation:

a. Here in this question, we are told that the total amount of fuel in the fuel tank is 11 gallons and the car consumes 0.75 gallon per hour. We are interested in knowing the amount of fuel left in the tank after driving for four hours.

We proceed as follows;

Since 0.75 gallon is consumed in an hour, the amount of fuel consumed in 4 hours would be the amount consumed in an hour * 4 hours

Mathematically, that would be 0.75 * 4 = 3 gallon

Now, the amount of fuel left is simply the difference between the initial amount of fuel in the tank minus the amount of fuel present after 4 hours.

That would be; 11 - 3 = 8 gallons

b. Like above, we want to know the amount of fuel left after t hours.

Since 0.75 is used up per hour, the amount used up in t hours would be 0.75 * t = 0.75t

Now, the amount of fuel that would be left in the tank would be the difference between what we had initially and what was used up.

Mathematically, that would be 11- 0.75t

Answer:

0

Step-by-step explanation:

We can use the slope formula to find the slope

m = (y2-y1)/(x2-x1)

    = ( -2 - -2)/( 4 -1)

    = (-2+2)/( 4-1)

    = 0/3

   = 0

Answer:

Step-by-step explanation:

[tex](1, -2) , (4, -2)\\m = ?\\x_1 =1\\y_1 =-2\\x_2 =4\\y_2 =-2\\\\m = \frac{y_2-y_1}{x_2-x_1} \\\\m = \frac{-2-(-2)}{4-1} \\m = \frac{-2+2}{3}\\ m = \frac{0}{3}\\ m = 0[/tex]

Answer:

B E

Step-by-step explanation:

Answer:

B. The mathematical domain is the set of real numbers, while the reasonable domain only includes real numbers greater than or equal to 0.

E. The mathematical range has a minimum value greater than 0, while the reasonable range is limited to whole numbers and has a minimum value greater than or equal to 500.

Step-by-step explanation:

Edge 2021

Answer

B. Sentence 2: Because included, and showed is the exact same thing so B

Step-by-step explanation:

Answer:

just so other guy can have brainlest

Step-by-step explanation:

Answer:

  -25, 25

Step-by-step explanation:

Since the numbers have the same absolute value and the sum of their absolute values is 50, they both must have an absolute value of 50/2 = 25.

Unique numbers with the same absolute value will have opposite signs.

The numbers are -25 and 25.

Answer:

The equation

[tex]4\,x^2-5=2\,(x+1)^2-7[/tex]

can be solved by first expanding all indicated operations, and later when the constant terms disappear, by factoring out 2x , leaving the equation as a product of two factors equal zero, from which it is easy to extract the roots. See below.

Step-by-step explanation:

When solving for x in the following expression, and using factoring to apply at the end the zero product theorem:

[tex]4\,x^2-5=2\,(x+1)^2-7\\4\,x^2-5=2\,(x^2+2x+1)-7\\4\,x^2-5=2\,x^2+4\,x+2-7\\4\,x^2-5=2\.x^2+4\,x-5\\4\,x^2=2\,x^2+4\,x\\4\,x^2-2\,x^2-4\,x=0\\2\,x^2-4\,x=0\\2\,x\,(x-2)=0[/tex]

We observe that for the last product, to get a zero, x has to be zero (making the first factor zero), or x has to be "2" making the binomial factor zero.

Answer: is brainly broken for u too??

Step-by-step explanation:

Complete question :

A pool holds 1440 cubic feet of water, the city charges $1.75 per cubic meter of water used.

How much will it cost to fill the pool?

Answer:

$71.36

Step-by-step explanation:

Amount charged per cubic meter = $1. 75

Total volume of pool = 1440 ft^3

Using the conversion unit chart :

1 cubic meter = 35.3147 cubic foot

Then we can express the capacity of water held by the pool in cubic metre.

If 1 cubic meter = 35.3147 cubic foot

Then ;

y cubic meter = 1440 cubic foot

y = 1440/35.3147

y = 40.776220 cubic meter

Thus;

Cost of filling the pool will be;

$1.75 × 40.776220

= $71.358386

= $71.36

Answer:

Integer, rational

Step-by-step explanation:

An integer is normally described as a positive and their opposites and zero. The explaination for blank 2 is a rational number because a rational number can also be an integer and a whole number. Hope this helps!

Answer:

Step-by-step explanation:

The answer is integer. Integer are whole numbers that are either positive or negative including 0.

Answer:

Rate of Change/Slope = -20

Equation: y= -20x +100

Step-by-step explanation:

A. We know the rate of change is also known as the slope.  If we used the slope formula to find the slope we can find the Rate of Change.

[tex]\frac{y2 - y1}{x2 - x1} = \frac{100-80}{1-2} = \frac{20}{-1} = -20[/tex]

B. Since we know the slope and 1 point on the graph we can substitute them in for 'b'

(0,100)

(100)=-20(0) + b

b = 100

Since we know the slope and the b value we can write the equation:\

y = -20x +100

The rate of change refers to the slope of the line, that is the change in y-axis per unit change in the value on the x-axis. Hence, the rate of change is :

Slope = - 100 / 5 = - 20

General form of a slope - intercept relation :

The intercept, c can be calculated thus:

100 = - 20(0) + c

100 = 0 + c

c = 100

Hence, the slope - intercept equation will be y = - 20x + 100

Learn more : https://brainly.com/question/18479471

Answer:

THE OTHER ANSWER IS WRONG

Step-by-step explanation:

90=20+6x-2

92=20+6x

72=6x

12=x

Hope this helps!

Answer:

15,10

Step-by-step explanation:

let the numbers be 3x and 2x

3x-2x=5

x=5

∴ numbers are 3×5,2×5

or 15,10

Complete question is;

For a data set of the pulse rates for a sample of adult​ females, the lowest pulse rate is 31 beats per​ minute, the mean of the listed pulse rates is x over bar equals 71.0 beats per​ minute, and their standard deviation is s equals 12.6 beats per minute.

a. What is the difference between the pulse rate of 31 beats per minute and the mean pulse rate of the​ females?

b. How many standard deviations is that​ [the difference found in part​ (a)]?

c. Convert the pulse rate of 31 beats per minutes to a z score.

d. If we consider pulse rates that convert to z scores between minus 2 and 2 to be neither significantly low nor significantly​ high, is the pulse rate of 31 beats per minute​ significant?

Answer:

A) 40 beats per minute

B) 3.1746

C) z = -3.17

D) the pulse rate of 31 beats per minute is significantly low.

Step-by-step explanation:

A) The mean pulse rate is given as x bar = 71

Thus difference between this and pulse rate of 31 beats per minute is;

Difference = 71 - 31 = 40 beats per minute

B) number of standard deviations of the difference found in part a is given as;

number = difference/standard deviation(s)

number = 40/12.6

number = 3.1746

C) The z-score is calculated from;

z = (x - xbar)/s

z = (31 - 71)/12.6

z = -3.17

D) from the question we are told that the z scores between minus2 and 2 to be neither significantly low nor significantly​ high. However, we have a Z-score of -3.17 which doesn't fall into that range. Thus, the pulse rate of 31 beats per minute is significantly low.

Answer:

c

Step-by-step explanation:

none of the above

C none of the above

because x-(-x)=x+x=2xand

-x+(-x)= -x-x=-2x

so answer is 'C' none of the above

they're equidistant, so distance should be equal.

distance of City centre is [tex]\sqrt{0^2+7^2}=7[/tex]

distance of mall is simply $x$. (ordinate is 0, means the point is on x axis , and that's the distance from origin)

thus, $$x=7$$

Answer:

Initial Value: 25, Rate of change -5.

First. Lets find the rate of change.

y2-y1/x2-x1 = m

We have A(1,20) B(3,10)

10-20/3-1=-5

m=-5(Rate of change)

Now let's find the initial value using slope-point form.

y-y₁=m(x-x₁)

y-20=-5(x-1)

=-5x+5+20

=-5x+25

The initial value is the value of y when the value of x is equal to 0. (Also the Y-Intercept)

Initial Value = -5(0)+25

=25

Answer:b

Step-by-step explanation:

Rocket science

Answer:

3(2x-5)(x+2)

Step-by-step explanation:

Factor out the 3.

3(2x²-x-10)

Factor the remaining.

3(2x-5)(x+2)

(I don‘t know what grid they’re talking about.)

Answer:The first issue one most notice is the words “at least” We are trying to find the probability of at least 2 girls.

The five possible outcomes for girls are 0,1,2,3,4. The odds of 1 girl out of 4 is .25 and the odds of 1 boy out of 4 is .25 (same as the odds of 3 out of 4 girls). Therefore the odds of 1 OR 3 girls must be .5 because 1 girl and 3 girls each has a .25 probability. If the probability of (1 OR 3 girls) equals .5, then the probability of 2 girls must be a different number.

The probability of 2 or more girls, is the sum of the probability of 4 girls (.06125)(—-.5 to the 4th power—— ), plus the probability of 3 girls (.25)——(the same as the probability of 1 boy)—- plus the probability of 2 girls. Since we know the probability of zero boys is .0625 (again, .5 to the 4th power) and the probability of 1 boy is .25 (the same as the probability of 3 girls )———then the probability of 2 girls is ((1 minus (the sum of the probability of 0 OR 1 boys) plus the (sum of the probability of 3 or 4 girls)), or 1-((.0625+.25)+(.0625+.25)), or .375. We had to derive the probability of two from the other known probabilities. Therefore .375+.25+.0625=.6875 is the probability of both AT LEAST 2 girls and also NO MORE than 2 boys. Notice this adds up to 1.375 because the probability of the central number 2 (i.e., .375) appears on both sides.

Answer:

Step 1: Address input parameters & values.

Input parameters & values:

The fraction number = 37/99

Step 2: Write it as a decimal

37/99 = 0.3737

0.3737 is the decimal representation for 37/99

Answer is 0.3737 repeating.

Hope this helps! Plz mark brainliest! ☜(ﾟヮﾟ☜)

Answer:

D

Step-by-step explanation:

(f+g)(x) = f(x) + g(x)

=3x + 9 + 5x²

=5x² + 3x + 9

Answer:

  A. (1, -2)

  B. the lines intersect at the solution point: (1, -2).

Step-by-step explanation:

A. The equations can be solve by substitution by using the y-expression provided by one of them to substitute for y in the other.

This gives ...

  3x -5 = 6x -8

Adding 8-3x to both sides, we get ...

  3 = 3x

Dividing both sides by 3 gives ...

  1 = x

Substituting this value into the first equation, we can find y:

  y = 3(1) -5 = -2

The solution is (x, y) = (1, -2).

__

B. The lines intersect at the solution point, the point that satisfies both equations simultaneously. That point is (1, -2).