Data Sufficiency

swerve wrote: ↑

Mon Jun 05, 2023 3:34 pm

How many people contributed to the Charity?

1. The average contribution to Charity \(Y\) was \(\$100\)

2. Charity \(Y\) collected a total of \(\$47,000\) in contributions

The OA is C

Source: Princeton Review

Target question: How many people contributed to Charity Y?

Statement 1: The average contribution to Charity Y was $100.
Clearly NOT SUFFICIENT

Statement 2: Charity Y collected a total of $47,000 in contributions.
Clearly NOT SUFFICIENT

Statements 1 and 2 combined
KEY CONCEPT: average contribution = (total amount of contributions)/(total number of people who contributed)
Let T = total number of people who contributed to Charity Y
Plug in other values to get: $100 = $47,000/T
Multiply both sides by T to get: 100T = 47,000
Divide both sides by 100 to get: T = 47,000/100 = 470
The answer to the target question is 470 people contributed to Charity Y
Since we can answer the target question with certainty, the combined statements are SUFFICIENT

Answer: C