An expression is shown. 2 3/4 x 2/3 What is the value of the expression?

The mean height of married American women in their early twenties is 64.5 inches and the standard deviation is 2.5 inches. The m

SSSSS [86.1K]

Answer:

The equation for regression line and predicting a husband's height for married couples in their early 20s

Equation: Y'=33.67+0.54*X'

Step-by-step explanation:

r=0.5

x'=64.5

Sx=2.5

y'=68.5

Sy=2.7

General regression line equation is:

Y'=a+b*X'

so the slope of the regression line is the linear correlation coefficient multiplied by the standard deviation for y' divided by the standard deviation for x'

$b=r*\frac{S_{y}}{S_{x}}\\b=0.5*\frac{2.7}{2.5}\\b=0.54$

The intercept with axis y is the mean of the decreased by the product of the slope and the mean of x

$a=y'-b*x'\\a=68.5-0.54*64.5\\a=33.67$

The equation regression line then is:

Y'=33.67+0.54*X'

4 0

3 years ago

Please help Ill give brainy pleas help please -

mars1129 [50]

The answer to this is a=3

4 0

1 year ago

Please Help!! Use Euler’s formula to write in exponential form.

LekaFEV [45]

Answer:

C, $4e^{i(7\pi/4)}$

Step-by-step explanation:

To remind you, Euler's formula gives a link between trigonometric and exponential functions in a very profound way:

$e^{ix}=\cos{x}+i\sin{x}$

Given the complex number $2\sqrt{2}-2i\sqrt{2}$ , we want to try to get it in the same form as the right side of Euler's formula. As things are, though, we're unable to, and the reason for that has to do with the fact that both the sine and cosine functions are bound between the values 1 and -1, and 2√2 and -2√2 both lie outside that range.

One thing we could try would be to factor out a 2 to reduce both of those terms, giving us the expression $2(\sqrt{2}-i\sqrt{2})$

Still no good. √2 and -√2 are still greater than 1 and less than -1 respectively, so we'll have to reduce them a little more. With some clever thinking, you could factor out another 2, giving us the expression $4\left(\frac{\sqrt{2}}{2} -i\frac{\sqrt{2}}{2}\right)$ , and now we have something to work with.

Looking back at Euler's formula $e^{ix}=\cos{x}+i\sin{x}$ , we can map our expression inside the parentheses to the one on the right side of the formula, giving us $\cos{x}=\frac{\sqrt2}{2}$ and $\sin{x}=-\frac{\sqrt2}{2}$ , or equivalently:

$\cos^{-1}{\frac{\sqrt2}{2} }=\sin^{-1}-\frac{\sqrt2}{2} =x$

At this point, we can look at the unit circle (attached) to see the angle satisfying these two values for sine and cosine is 7π/4, so $x=\frac{7\pi}{4}$ , and we can finally replace our expression in parentheses with its exponential equivalent:

$4\left(\frac{\sqrt2}{2}-i\frac{\sqrt2}{2}\right)=4e^{i(7\pi/4)}$

Which is c on the multiple choice section.

4 0

3 years ago

Gerald earns $14.50 per hour. His regular hours are 40 hours per week, and he receives time-and-a-half overtime. Find his total

shtirl [24]

Answer:

Gerald Pali per hawa his regular house are 40 hours per week and there was a time and a half overtime find the total pay of a week in which he were 24 hours

Step-by-step explanation:

5 0

2 years ago

I will mark as brainliest Do 1-9

dangina [55]

To solve this problem, we need to know the formulas for the areas of each of these shapes. The formula for the area of a circle is πr², the area of a rectangle is b * h, the area for a square is s², and the area for a triangle is 0.5bh. Now we can solve.

1) This is a circle, so the area is πr² = π(6)² = 36π square feet

2) This is a square, so the area is s² = 12² = 144 square yards

3) This is a rectangle, so the area is b * h = 6 * 14 = 84 square inches

4) This is a rectangle, so the area is b * h = 7 * 3 = 21 square inches

5) This is a circle, so the area is πr² = π(4)² = 16π square feet

6) This is a triangle, so the area is 0.5bh = 0.5 (8 * 8) = 0.5 * 64 = 32 yd.²

7) This is a triangle, so the area is 0.5bh = 0.5 (5 * 10) = 50 * 0.5 = 25 yd.²

8) This is a rectangle, so the area is b * h = 10 * 2 = 20 in²

9) This is a square, so the area is s² = 9² = 81 ft²

5 0

3 years ago

An expression is shown.2 3/4 x 2/3What is the value of the expression?​

An expression is shown.2 3/4 x 2/3What is the value of the expression?