Our goal is to run a mean of 45 minutes per day for a week. for the first six days, you run 38, 40, 40, 42, 43, and 50 minutes. how many minutes must you run on the seventh day to reach your goal exactly? 28 minutes 62 minutes 4216 minutes 17 minutes

62 minutes.

Step-by-step explanation:

To find the mean, you need to add together all of your values (the minutes) and divide them by the number of values (how many sets of minutes given).

So, choosing to add 62 minutes:

38 + 40 + 40 + 42 + 43 + 50 + 62 = 315

There are 7 sets of minutes in total, so we then divide 315 by 7.

315/7 = 45 minutes

Therefore, running 62 minutes on the seventh day would cause you to run a mean of 45 minutes per day for the week.

(b) 240

step-by-step explanation:

first, we use the pythagorean formula using the given side lengths to find x. then we use x to find the side lengths. then we add the side lengths to find the perimeter.

pythagorean theorem formula:

a^2 + b^2 = c^2

(x - 20)^2 + (x - 40)^2 = x^2

x^2 - 40x + 400 + x^2 - 80x + 1600 = x^2

x^2 -120x + 2000 = 0

(x - 100)(x - 20) = 0

x - 100 = 0 or x - 20 = 0

x = 100 or x = 20

we see that the solution x = 20 must be discarded because it will give a negative side length and a side length of 0. the only valid solution is x = 100.

perimeter = sum of the lengths of the sides

perimeter = x + x - 20 + x - 40

perimeter = 3x - 60

replace x with 100.

perimeter = 3(100) - 60

perimeter = 300 - 60

perimeter = 240