Difficulty: Easy
Correct Answer: 49
Explanation:
Introduction / Context:
When two square roots are equal, their radicands (nonnegative) must be equal. We simplify one side and equate the interior fractions to find the missing numerator.
Given Data / Assumptions:
Concept / Approach:
First simplify 25/15625. Then set the simplified fraction equal to ?/30625 and solve for the unknown numerator.
Step-by-Step Solution:
Verification / Alternative check:
Compute √(?/30625) with ? = 49: 49/30625 = 1/625; √(1/625) = 1/25, matching the left side.
Why Other Options Are Wrong:
Common Pitfalls:
Equating the square roots without equating the radicands, or forgetting to simplify 25/15625 first.
Final Answer:
49
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