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Averages: The Average Pie

What was the average production rate of cups of espresso per machine for Machines A, B, C, and D last week? >(1) Machines A and D produced a total of 503 cups of espresso last week. >(2) Machines B and E produced a total of 405 cups of espresso last week.
Correct.

[[snippet]]

Statement (1) only has the number of cups for machines A and D, so (1) Insufficient → BCE. Statement (2) has the number of cups for Machines B and E. E is not mentioned in the question stem as one of the machines we need the average for, and in any case, we don't know the total of the other machines when reading (2) alone. So (2) Insufficient → CE.

Combining both statements still does not yield the total number of espresso cups for the four Machines A, B, C, and D, so (1)+(2) Insufficient → E.
Incorrect. [[snippet]] Statement (1) only has the number of cups for Machines A and D, so (1) Insufficient → BCE.
Incorrect. [[snippet]] Statement (2) tells us nothing but the number of cups for Machines B and E (and where did Machine E come from?), so (2) Insufficient → ACE.
Did you mistake Machine E for Machine C?
Read and re-read the problem before you take your pick, to avoid careless mistakes.
Incorrect. [[snippet]] Each statement alone only has the total cups for two of the coffee machines.
You are not given any information about Machine C, so you are unable to determine the total number of cups for Machines A, B, C, and D.
Incorrect. [[snippet]] Combining both statements still does not yield the total number of cups of espresso for Machines A, B, C, and D.
Statement (1) ALONE is sufficient, but Statement (2) alone is not sufficient to answer the question asked.
Statement (2) ALONE is sufficient, but Statement (1) alone is not sufficient to answer the question asked.
BOTH Statements (1) and (2) TOGETHER are sufficient to answer the question asked, but NEITHER statement ALONE is sufficient to answer the question asked.
EACH statement ALONE is sufficient to answer the question asked.
Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked, and additional data specific to the problem are needed.
Doh! Now how did that happen?
No I didn't.
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