How am i supposed to make a function? number 15

Part A

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Work Shown:

1800 = initial cost or starting cost

58*1 = 58 = cost for one person

58*2 = 116 = cost for two people

58*n = cost for n people

58n+1800 = total cost

58n+1800 = T(n)

T(n) = 58n+1800

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Part B

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Work Shown:

T = total bill

15% discount means you still pay 85% of the bill (85%+15% = 100%)

D = discounted cost

D = 85% of T

D = 0.85*T

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Part C

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Work Shown:

We combine parts A and B.

T(n) = 58n+1800 from part A

D(T) = 0.85*T from part B

D(T(n)) = 0.85*( T(n) )

D(T(n)) = 0.85*( 58n+1800 ) ... plug in T(n) = 58n+1800

D(T(n)) = 0.85*( 58n+1800 )

D(T(n)) = 0.85*(58n)+0.85*(1800) ... distribute

D(T(n)) = 49.3n + 1530

If we plugged in n = 0, then,

D(T(n)) = 49.3n + 1530

D(T(0)) = 49.3*0 + 1530

D(T(0)) = 1530

Or we could plug n = 0 into T(n) to get T(0) = 1800

Then plug T = 1800 into D(T) = 0.85*T to get D(1800) = 1530

Either way you'll get the same answer.

Repeat this (using either method) for n = 50, 100, 150, 200 and you'll get the table of values you see below in the attached image.

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Part D

The D( T(n) ) function allows us to find the discounted cost D for any number n of people that show up.

The input is n, where n is some positive integer less than or equal to 200 (because this is the reception hall's max capacity).

The output is the final discounted cost.

Example: n = 50 is one input which leads to its corresponding output of D( T(n) ) = 3995 as the table shows. So 50 people would have a discounted total cost of $3,995.

#12 the answer is the third option