The total cost function is the sum of the two given functions, and this is equal to:
c(t) = 190 + 70*t
We know that:
If she hires both of them for the same time t, then the total cost function will be given by the sum of the two above functions, we will get:
c(t) = p(t) + e(t)
c(t) = (115 + 25*t) + (55*t + 75)
c(t) = (115 + 75) + (55*t + 25*t)
c(t) = 190 + 70*t
If you want to learn more about linear functions, you can read:
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