What is the least positive integer by which 1470 must be multiplied to make it a perfect square?
Answer and explanation
Correct answer: D. 30
- Step 1: Prime factorize 1470: 1470 = 10 147 = 2 5 3 49 = 2 3 5 * 7^2.
- Step 2: For a perfect square, all exponents must be even. The factors 2, 3, and 5 have exponent 1.
- Step 3: Multiply by 2 3 5 = 30.
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