Difficulty: Easy
Correct Answer: .6241
Explanation:
Introduction / Context:We are reversing a square-root operation to recover the missing addend inside the radical. This is a standard technique in quantitative aptitude involving squaring both sides carefully.
Given Data / Assumptions:
Concept / Approach:Square both sides to eliminate the square root, then isolate N. The arithmetic requires precise decimal squaring of 8.71.
Step-by-Step Solution:
Square the right-hand side: 8.71^2 = 75.8641.Thus, 75.24 + N = 75.8641.N = 75.8641 − 75.24 = 0.6241.Verification / Alternative check:Check: 75.24 + 0.6241 = 75.8641 and √75.8641 = 8.71 exactly.
Why Other Options Are Wrong:
Common Pitfalls:Mis-squaring 8.71 or mishandling decimal subtraction can lead to place-value mistakes.
Final Answer:.6241
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