Hi ajca,
This DS question is built on "system" Algebra, without any of the factors/multiples shortcuts that are common on DS versions of these questions.
We're asked for the total price of 2 sandwiches and 3 cans of soda.
**Note: When translating the Facts into Algebra, I'm going to use....
W = # of sandwiches
C = # of cans of soda
The question asks us for 2W + 3C
Fact 1: 1 sandwich and 1 can of soda = $3
W + C = 3
This is 1 equation with 2 variables, so there's no way to figure out the answer to the question. Here's the proof:
IF....
W = 1
C = 2
Then the answer to the question is 2(1) + 3(2) = 8
IF.....
W = 2
C = 1
Then the answer to the question is 2(2) + 3(1) = 7
Fact 1 is INSUFFICIENT
Fact 2: 3 sandwiches and 2 cans of soda = $8
We have a similar situation to what we have in Fact 1: 1 equation and 2 variables.....
3W + 2C = 8
IF....
W = 2
C = 1
Then the answer to the question is 2(2) + 3(1) = 7
IF....
W = 1
C = 2.5
Then the answer to the question is 2(1) + 3(2.5) = 9.5
Fact 2 is INSUFFICIENT
Combined, we have...
W + C = 3
3W + 2C = 8
This is a "system" - 2 variables and 2 unique equations, which means that we CAN solve for the values of W and C (and then answer the question.
Combined, SUFFICIENT
Final Answer:
GMAT assassins aren't born, they're made,
Rich