Problem Solving

Hi Vincen,

This question question is an example of a 'system' algebra question - but it can actually be solved in a variety of different ways, including Algebraically and by TESTing THE ANSWERS. If you recognize the ratio that exists begin the two sizes of cans, then you can also use that pattern to your advantage...

6 (25-ounce cans) = 150 ounces
10 (15-ounce cans) = 150 ounces

You can use THAT ratio (6:10) to work through this question relatively quickly...
6 and 10 = 4 more of the smaller cans
12 and 20 = 8 more of the smaller cans
18 and 30 = 12 more of the smaller cans
Etc.

We're told that the number of smaller cans that are needed would be 40 more than the number of larger cans. That would be...
6(10) and 10(10) =
60 and 100 = 40 more smaller cans

100 smaller cans would be needed

Final Answer: D

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

Vincen wrote:Each week a restaurant serving Mexican food uses the same volume of chili paste, which comes in either 25-ounce cans or 15-ounce cans of chili paste. If the restaurant must order 40 more of the smaller cans than the larger cans to fulfill its weekly needs, then how many smaller cans are required to fulfill its weekly needs?

A) 60
B) 70
C) 80
D) 100
E) 120

We can let the number of 25-ounce cans = x, and thus the number of 15-ounce cans = x + 40 and we can create the following equations:

25x = 15(x + 40)

25x = 15x + 600

10x = 600

x = 60

We see that we need 60 larger cans of chili paste. Since the number of smaller cans of chili paste is 40 more than the number of larger cans of chili paste, we need 100 smaller cans of chili paste.

Answer: D