Alan repairs televisions. His revenue is modeled by the function R(h)=47+2h for every h hours he spends repairing televisions. His overhead cost is modeled by the function C(h) = 5h² – 25 dollars. After how many hours does he break even?

  4

Step-by-step explanation:

Alan's cost and revenue are the same when ...

  R(h) = C(h)

  47 +2h = 5h^2 -25

  0 = 5h^2 -2h -72

  0 = (5h +18)(h -4)

The expression on the right will be zero for h = -3.6 and h = 4. We are only interested in the positive value.

Alan will break even after 4 hours.

_____

After 4 hours, Alan's costs exceed his revenue.

hello,

b) 62.47% of the students are between 14 and 18 years old.

step-by-step explanation:

mean = 15 and standard deviation = 2

student between 14 to 18

formula used z-score

for age 14 , z score

using z-table , p(z> -0.5)=0.3085

for age 18 , z score

using z-table , p(z< 1.5)=0.9332

p(-0.5< z< 1.5)=0.9332-0.3085 = 0.6247

thus, 62.47% of the students are between 14 and 18 years old.

click to let others know, how is it

0.0

0 votes

1

report

read more on -

step-by-step explanation: