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For a recent year, the cost C (in $) for tuition and fees for x credit-hours at a public college was given by C= 162.15x-91.

(a) Determine the cost to take 14 credit-hours. Round to the nearest cent.
(b) If Jenna spent $1854.80 for her classes, how many credit-hours did she take? "

User Jarjar
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1 Answer

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Final answer:

To answer part (a), we substitute x with 14 in the equation C = 162.15x - 91, and calculate the cost as $2,179.10. For part (b), we rearrange the equation to solve for x and determine that Jenna took approximately 12 credit-hours when she spent $1854.80.

Step-by-step explanation:

The question requires us to use the linear equation C = 162.15x - 91 to calculate the costs for tuition and fees for a given number of credit-hours at a public college. This equation represents a function where C is the cost in dollars and x is the number of credit-hours.

Part (a)

To determine the cost to take 14 credit-hours, we substitute x with 14 in the equation. The calculation is as follows:

C = 162.15(14) - 91

C = 2270.10 - 91

C = 2179.10

Therefore, the cost to take 14 credit-hours round to the nearest cent is $2,179.10.

Part (b)

To find out how many credit-hours Jenna took when she spent $1854.80, we rearrange the equation to solve for x:

C + 91 = 162.15x

Substituting C with $1854.80:

$1854.80 + 91 = 162.15x

$1945.80 = 162.15x

x ≈ $1945.80 / 162.15

x ≈ 12

Jenna took approximately 12 credit-hours.

User Felix Almesberger
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