GRE General TestQuantitative ReasoningEasy
A quality control engineer is inspecting a batch of 800 electronic components. He finds that 5% of the components are defective. How many components are NOT defective?
- A800
- B760
- C795
- D40
Show answer & explanationAnswer & explanation
Correct answer: B. 760
To find the number of non-defective components, first calculate the number of defective components and then subtract that from the total. Alternatively, calculate the percentage of non-defective components and multiply by the total.
Why the other options are wrong
- A. This is the total number of components, not the non-defective count.
- C. This incorrectly subtracts 5 from the total instead of 5% of the total.
- D. This is the number of defective components, not non-defective.
Percentage of a Quantity
To find a percentage of a quantity, convert the percentage to a decimal or fraction and multiply it by the quantity.
- Percentage means 'out of 100'.
- Can be used to find a part of a whole.
- Often involves converting between percentages, decimals, and fractions.
Memory trick: Percent Part Power: Find the part by multiplying the percent (decimal) by the total.