SAT Math: Find what percent one number is of another
27+ practice questions in Praczo
The concept, explained
- 1
To find what percent A is of B: (A / B) × 100. Always put the "is" value (A) on top and the "of" value (B) on the bottom.
- 2
Read the question carefully. "15 is what percent of 60?" means A = 15, B = 60: (15/60) × 100 = 25%.
- 3
For real-world contexts, identify which quantity is the reference (the "of"). Sales tax is a percent of the original price, not of the total.
- 4
Double-check by asking: "Does my percent sound reasonable?" 50% should be half the reference; 200% should be double.
- ✗ Flipping the fraction: putting the reference value on top and the part on the bottom.
- ✗ Forgetting to multiply by 100, reporting the decimal as the percent.
SAT-style practice
A student answered 42 questions correctly out of 56 total. What percent did the student answer correctly?
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