The amount of time it takes a student from Denali to do a statistics activity follows the Normal distribution with a
mean of 25 minutes and a standard deviation of 5
minutes. Students at K2 complete a statistics activity with
a mean time of 20 minutes and have a standard deviation
of 8 minutes.
b) What is the standard deviation of the difference of their
scores?

AP stats hw, thank you!

step-by-step explanation:

there is a formula i can give you:

it is r^2*n*sin(360/n) divided by 2 where r represents the "radius" and n is the number of sides.

plug them in:

(10sqrt(3))^2*6*sin(360/6) divided by 2

100*3*6*sin(60) divided by 2

900*sin(60)

900*sqrt(3)/2

450*sqrt(3)

approx is 779.4 cm^2

5   1/4   miles per hour

step-by-step explanation:

15   3/4 / 3 = 5   1/4

this is a direct variation proportion. y = kx

y is the total amount due, k is the constant of variation, and x is the number of texts sent.

plug in the 3.20 and the 16 to solve for the "k". this is the constant of proportionality. it is the value that will not change.

3.20 = k(16). solving you get $.20 per text.

the equation would then be y = .20x