Hi jjjinapinch,

We're told that Jim receives a monthly base salary plus a 10% commission on the price of each car he sells that month. We;re told that Jim sold 15 cars last month. We're asked for the total amount of base salary and commissions that Jim received that month. To answer this question, we'll need to know the base salary and the sum of those 15 commissions.

1) Last month, Jim's base salary was $3,000.

Fact 1 tells us the base salary, but tells us NOTHING about the 15 car sales/commissions.
Fact 2 is INSUFFICIENT

2) Last month, Jim sold 3 cars whose prices totaled $60,000 and 5 cars whose prices totaled $120,000.

Fact 2 gives us information on just 8 of the 15 car sales. It doesn't tell us about the base salary nor does it tell us about the remaining 7 sales/commissions.
Fact 2 is INSUFFICIENT

Combined, we still don't know anything about the remaining 7 cars that Jim sold, so there's no way to determine the commissions on those sales and there's no way to determine the total pay that Jim received.
Combined, INSUFFICIENT

Final Answer: E

GMAT assassins aren't born, they're made,
Rich

jjjinapinch wrote:Each month, Jim receives a base salary plus a 10 percent commission on the price of each car he sells that month. If Jim sold 15 cars last month, what was the total amount of base salary and commissions that Jim received that month?
(1) Last month, Jim's base salary was $3,000.
(2) Last month, Jim sold 3 cars whose prices totaled $60,000 and 5 cars whose prices totaled $120,000

To show Jim's salary and commissions last month, we can create an equation in which n = his base salary and p = his total car sales:

Total salary = n + 0.1p

Total = n + 0.1p

Statement One Alone:

Last month, Jim's base salary was $3,000.

We have:

Total = 3,000 + 0.1p

Since we cannot determine his total car sales, statement one alone is not sufficient to answer the question.

Statement Two Alone:

Last month, Jim sold 3 cars whose prices totaled $60,000 and 5 cars whose prices totaled $120,000.

Since we are given information about only 8 of the 15 cars, we do not know the total sales of the remaining 7 cars, and thus we don't know the value of p. Furthermore, we do not know the value of n. Thus, statement two alone is not sufficient to answer the question.

Statements One and Two Together:

Using the statements together, we still cannot determine the value of p, and thus we cannot determine his total salary last month.

Answer: E