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3 years ago

5

Suppose x has a normal distribution with mean μ = 45 and standard deviation σ = 9. describe the distribution of x values for sam

ple size n = 4. (round σx to two decimal places.) μx = σx =

1 answer:

Fofino [41]3 years ago

4 0

The standard deviation of a particular sample is equal to the standard deviation divided by the square root of the sample size. That is, $\sigma_x=\frac{\sigma}{\sqrt n}$
The mean of a particular sample is equal to the mean of the set the sample was taken from. That is,
$\mu_x=\mu$
$\text{In your case, }\sigma_x=\frac{9}{\sqrt4}=\frac92\text{ and }\mu_x=45.$

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2 years ago

An apartment complex has a floor plan with dimensions shown. To effectively air condition a room, 20 BTU’s are required for ever

kifflom [539]

12,900 BTU's are required to cool the room effectively.

Step-by-step explanation:

Step 1:

We must calculate the area of the entire shape to determine the minimum BTU's required to cool the room effectively.

It is made up of a semi-circle a rectangle, and a trapezoid.

Step 2:

The area of a semi-circle $=\frac{ \pi r^{2} }{2} .$

Here, the diameter is 20 feet so the radius is 10 feet.

The area of the semi-circle $=\frac{ \pi r^{2} }{2} =\frac{ (\pi) (10^{2}) }{2} = 157.079$ square feet.

The area of a rectangle $= (l)(w).$

The length of the rectangle is 22 feet and the width is 20 feet.

The area of a rectangle $= (l)(w) =(22)(20) = 440$ square feet.

The area of a trapezoid $=\frac{a+b}{2} (h).$

Here $a=12, b= 20, h= 3$ .

The area of a trapezoid $=\frac{12+20}{2} (3) = 48$ square feet.

Step 3:

The total area of the floor plan $=157.079+440+48 = 645.079$ square feet.

If 20 BTU's are required for a single square foot,

The number of BTU's for 645.079 square feet $= (645.079)(20)=12,901.58$ BTU's.

Rounding this off, we get 12,900 BTU's required to cool the room effectively.

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3 years ago

34.8 x 0.007 basic math

ra1l [238]

0.2436 is the answer

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3 years ago

Read 2 more answers

On the horizontal number line show how you will round 198.78 to the tens place & write the rounded number. Given picture is

harkovskaia [24]

If the three slashes are 190, 195, and 200, we can see it as
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7 0

3 years ago

If 47400 dollars is invested at an interest rate of 7 percent per year, find the value of the investment at the end of 5 years f

Anni [7]

Answer:

Part A) Annual $\$66,480.95$

Part B) Semiannual $\$66,862.38$

Part C) Monthly $\$67,195.44$

Part D) Daily $\$67,261.54$

Step-by-step explanation:

we know that

The compound interest formula is equal to

$A=P(1+\frac{r}{n})^{nt}$

where

A is the Final Investment Value

P is the Principal amount of money to be invested

r is the rate of interest in decimal

t is Number of Time Periods

n is the number of times interest is compounded per year

so

Part A) Annual

in this problem we have

$t=5\ years\\ P=\$47,400\\ r=0.07\\n=1$

substitute in the formula above

$A=\$47,400(1+\frac{0.07}{1})^{1*5}$

$A=\$47,400(1.07)^{5}$

$A=\$66,480.95$

Part B) Semiannual

in this problem we have

$t=5\ years\\ P=\$47,400\\ r=0.07\\n=2$

substitute in the formula above

$A=\$47,400(1+\frac{0.07}{2})^{2*5}$

$A=\$47,400(1.035)^{10}$

$A=\$66,862.38$

Part C) Monthly

in this problem we have

$t=5\ years\\ P=\$47,400\\ r=0.07\\n=12$

substitute in the formula above

$A=\$47,400(1+\frac{0.07}{12})^{12*5}$

$A=\$47,400(1.0058)^{60}$

$A=\$67,195.44$

Part D) Daily

in this problem we have

$t=5\ years\\ P=\$47,400\\ r=0.07\\n=365$

substitute in the formula above

$A=\$47,400(1+\frac{0.07}{365})^{365*5}$

$A=\$47,400(1.0002)^{1,825}$

$A=\$67,261.54$

8 0

3 years ago