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Nimfa-mama [501]

4 years ago

14

Find a number whose product with 3 is same as it sum with 30

1 answer:

Allushta [10]4 years ago

6 0

X (3) = x + 30

3x = x + 30

Subtract x from both sides

2x = 30

X = 15

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4 yards to 30 inches write each ratio in simplest form

MissTica

Answer:

24:5

Step-by-step explanation:

4 yards is 3 feet, so 4*3=12. There are 12 inches in a foot, so 12*12=144. 144:30= 72:15 = 24:5

6 0

3 years ago

Given a sample size n, how will the distribution of the sample mean behave?

Keith_Richards [23]

Answer:
Provided that the sample size, n, is sufficiently large (greater than 30), the distribution of sample means selected from a population will have a normal distribution, according to the Central Limit Theorem.

Explanation:
1. As n increases, the sample mean approaches the population mean
(The Law of Large numbers)
2. The standard error of the sample is
σ/√n
where σ = population standard deviation.
As n increases, the standard error decreases, which means that the error
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5 0

3 years ago

There are 7 males and 5 females and we need to select 4 different people. how many ways can we select 4 people?

saul85 [17]

$\displaystyle \binom{12}{4}=\dfrac{12!}{4!8!}=\dfrac{9\cdot10\cdot11\cdot12}{2\cdot3\cdot4}=495$

5 0

3 years ago

A Norman window has the shape of a semicircle atop a rectangle so that the diameter of the semicircle is equal to the width of t

Makovka662 [10]

Answer:

132.233 ft2

Step-by-step explanation:

Let's call the width of the rectangle 'w' and the length 'x'. So the area of the semicircle is:

$A_1 = \pi*radius^2/2$

$A_1 = \pi*(w/2)^2/2$

$A_1 = \pi/8*w^2$

And the area of the rectangle is:

$A_2 = w*x$

If the perimeter of the window is 41 feet, we have:

$Perimeter = length + 2*width + \pi*radius$

$41 = x + 2*w + \pi*w/2$

$x = 41 - w(2 + \pi/2)$

Now, the equation for the total area of the window is:

$A = A_1 + A_2 = \pi/8*w^2 + w*x$

$A = \pi/8*w^2 + w*(41 - w(2 + \pi/2))$

$A = (\pi/8-2 - \pi/2)*w^2 + 41w = -3.1781w^2 + 41w$

To find the maximum area, we can find the x-coordinate of the vertex of the quadratic equation:

$x\_vertex = -b / 2a = -41 / (-3.1781*2) = 6.45$

So the width that gives us the maximum area of the window is 6.45 feet, and the area will be:

$A = -3.1781w^2 + 41w = -3.1781*(6.45)^2 + 41*6.45 = 132.233\ ft^2$

3 0

3 years ago

The sum of one-third of a number and three-fourths of the number exceeds that number by one. Which equation could be used to fin

Marrrta [24]

$\frac{n}{3} + \frac{3n}{4} = n+1 
$
$4n + 9n = n+1$
$13n = n+1$
$13n-n = 1$
$12n = 1$

8 0

3 years ago

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