It costs x dollars each to make the first 1,000 copies of a compact

Question

It costs x dollars each to make the first 1,000 copies of a compact disc and y dollars to make each subsequent copy. If z is greater than 1,000, how many dollars will it cost to make z copies of the compact disc?

(A) 1,000x + yz
(B) zx – zy
(C) 1,000 (z – x) + xy
(D) 1,000 (z – y) + xz
(E) 1,000 (x – y) + yz

(A) 1,000x + yz
(B) zx – zy
(C) 1,000 (z – x) + xy
(D) 1,000 (z – y) + xz
(E) 1,000 (x – y) + yz

GMAce93 · Answer

Total no. of copies to be made =z 
Given z > 1000 
Cost for making first 1000 copies = 1000x 
Remaining copies = z-1000
Cost for remaining copies = (z-1000)y
Total cost = 1000x+ (z-1000)y = 1000(x-y)+yz
 Option E.

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generis · Answer

Let x = $2
First 1000 discs cost
$2 * 1000 =  $2000

Let z, total # of discs = 1500

Let y, cost/disc after first 1000 discs = $1

# of discs after first 1000
1500 - 1000 = 500 left
Cost of those 500 at y=$1:
500 * 1 =  $500

Overall cost: 2000 + 500 =  2500

Find the answer that = 2500
Use x = 2, y = 1, z = 1500

(A) 1,000x + yz
(1000)(2) + (1)(1500) =
2000+1500 = 3500. Too large. NO

(B) zx – zy
(1500)(2) - (1500)(1) =
3000-1500 = 1500. Too small. NO

(C) 1,000 (z – x) + xy
1000(1500-2) + (2)(1)
1000(1498) + 2 = huge. Stop. NO

(D) 1,000 (z – y) + xz
1000(1500-1) + (2)(1500)=
1000(1499) + 3000 = huge. Stop. NO

(E) 1,000 (x – y) + yz
1000(2-1) + (1)(1500) =
1000(1) + 1500 = 2500. MATCH

Answer E

Plunkster82 · Answer

I got E, but this is one where I, again, need to read the problem better. I misread the question and didn't realize x is the price per copy for the first thousand. I thought X was total cost, which led me to X + (Z-1000)*Y, which thankfully isn't an answer.

So I regrouped and realized X is price per copy. 
-1000x is the cost of the first 1,000 copies. 
-y*(z-1,000) is the cost for every copy after the first 1,000.
-But 1,000x+y*(z-1,000), isn't an answer. 
-So I broke expanded outside the parentheses to get 1,000x+yz-1,000y. 
-Regrouped the terms to read 1,000x-1,000y+yz. 
-Factored out 1,000(x-y)+yz, which is an answer.

ScottTargetTestPrep · Answer

The cost is:

1000x + y(z - 1000)

1000x + yz - 1000y

1000(x - y) + yz

Answer: E

bumpbot · Answer

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It costs x dollars each to make the first 1,000 copies of a compact

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It costs x dollars each to make the first 1,000 copies of a compact

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