Last Updated on May 9, 2023
GMAT OFFICIAL GUIDE DS
Solution:
We are given that a salesman is paid $300, plus a commission equal to 5 percent of the amount of his sales over $1,000. If we set variable T as the total amount of his sales and A as the amount he earned last week, we can create the following equation:
A = 300 + 0.05(T – 1,000)
We need to determine the value of A.
Statement One Alone:
The total amount the salesman was paid last week is equal to 10 percent of the amount of his sales last week.
Using the information we can create the following equation:
A = 0.1T
Since A = 0.1T, we can substitute 0.1T for A in the equation A = 300 + 0.05(T – 1,000).
0.1T = 300 + 0.05T – 50
0.05T = 250
5T = 25,000
T = 5,000
Since we have a value for T, we can determine A.
A = 300 + 0.05(5,000 – 1,000)
A = 300 + 0.05(4,000)
A = 300 + 200
A = 500
Statement one is sufficient to answer the question. We can eliminate answer choice B, C, and E.
Statement Two Alone:
The salesman’s sales last week totaled $5,000.
Once again, since we have a value for T, we can determine the value of A. Statement two is sufficient to answer the question.
Answer: D
