Problem Solving

AAPL wrote:During one day, a door-to-door brick salesman sold three-fourths of his bricks for $0.25 each. If he had 150 bricks left at the end of the day, how much money did he collect for brick sales that day?

A. $12.50
B. $37.50
C. $50.00
D. $112.50
E. $150.00

If 3/4 of the bricks were SOLD, then the remaining bricks (1/4 of the bricks) were NOT SOLD.

If 150 = 1/4 of the bricks, then 450 = 3/4 of the bricks
In other words, the salesman sold 450 bricks
If 450 bricks were sold at $0.25, then the money collected = (450)($0.25) = $112.50

Answer: D

Cheers,
Brent

Hi AAPL,

We're told that a brick salesman sold 3/4 of his bricks for $0.25 each and that he had 150 bricks left at the end of the day. We're asked for the amount of money that he collected for brick sales that day.

Most Test Takers will calculate the number of bricks sold and then multiply by $0.25 - which is a logical way to approach the prompt. There are other ways to get to the correct answer though. We know that the 150 bricks represent 1/4 of the total bricks. THOSE 150 bricks, if sold, would have generated (150)($0.25) = $37.50. Three times that number were sold though (since 3/4 is '3 times' 1/4), so the revenue from the sold bricks is (3)($37.50) = $112.50. Based on how 'spread out' the Answers are, you don't even have to complete that entire calculation - since (3)($30) = $90, we know the total will be a bit higher than that.

Final Answer: D

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

AAPL wrote:During one day, a door-to-door brick salesman sold three-fourths of his bricks for $0.25 each. If he had 150 bricks left at the end of the day, how much money did he collect for brick sales that day?

A. $12.50
B. $37.50
C. $50.00
D. $112.50
E. $150.00

We see that 150 bricks he had left at the end of the day must be 1/4 of all the bricks he had at the beginning of the day. Thus he had 150 x 4 = 600 bricks at the beginning of the day, and, during the day, he sold 3/4 x 600 = 450 bricks. Since each brick is $0.25, he sold a total of 450 x 0.25 = $112.50 worth of bricks.

Answer: D