Mo2men wrote:A factory has three types of machines - A, B, and C - each of which works at its own constant rate. How many widgets could one machine A, one Machine B, and one Machine C produce in one 8-hour day?
(1) 7 Machine A's and 11 Machine B's can produce 250 widgets per hour
(2) 8 Machine A's and 22 Machine C's can produce 600 widgets per hour
Sweet question!
Target question: How many widgets could one machine A, one Machine B, and one Machine C produce in one 8-hour day?
Statement 1: 7 Machine A's and 11 Machine B's can produce 250 widgets per hour
No information about Machine C
NOT SUFFICIENT
Statement 2: 8 Machine A's and 22 Machine C's can produce 600 widgets per hour
No information about Machine B
NOT SUFFICIENT
Statements 1 and 2 combined
Statement 1:
7 Machine A's and 11 Machine B's can produce 250 widgets per hour
Statement 2: 8 Machine A's and 22 Machine C's can produce 600 widgets per hour
Hmmm, I see that we're given info about 11 Machine Bs and 22 Machine Cs. Perhaps we might gain some useful information, if we create an EQUIVALENT statement such that Machines B and C produce the SAME number of widgets.
Take statement 2 and HALVE everything to get:
4 Machine As and 11 Machine Cs can produce 300 widgets per hour
Combine this new (equivalent) info with statement 1 to see we have two useful pieces of info:
7 Machine A's and 11 Machine B's can produce 250 widgets per hour
4 Machine As and 11 Machine Cs can produce 300 widgets per hour
So, if we ADD all of the machines we get:
11 Machine A's, 11 Machine B's and 11 Machine C's can produce 550 widgets per hour
Now divide everything by 11 to get:
1 Machine A, 1 Machine B and 1 Machine C can produce 50 widgets per hour
So,
1 Machine A, 1 Machine B and 1 Machine C can produce 400 widgets in 8 hours
Since we can answer the
target question with certainty, the combined statements are SUFFICIENT
Answer =
C
RELATED VIDEO
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https://www.gmatprepnow.com/module/gmat ... /video/917
