Two positive whole numbers have a sum of 25 and a product of 144. What is the larger number?
Answer and explanation
Correct answer: D. 16
- Step 1: List factor pairs of 144: 1 × 144, 2 × 72, 3 × 48, 4 × 36, 6 × 24, 8 × 18, 9 × 16, 12 × 12. Step 2. Only 9 + 16 = 25. Step 3. The larger number is 16. Answer: 16. Why not the others: 9: This is the smaller of the two numbers. 12: This is the square root of 144, which is the answer only when both numbers are equal. 13: This is half of 25 rounded up, which would give a product of 156.
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