Difficulty: Easy
Correct Answer: None of these
Explanation:
Introduction / Context:
This question tests conversion between mixed numbers and decimals and then finding exact square roots. Recognizing perfect decimal squares can speed up calculations.
Given Data / Assumptions:
N = 11 9/16 = 11 + 9/16.
Concept / Approach:
Convert 9/16 to decimal (0.5625). Then N = 11.5625. If you know that 3.4^2 = 11.56 and 3.4 = 17/5, you can check exactness. Here 3.4^2 = 11.56; N is 11.5625 which equals 3.4^2 + 0.0025 = (3.4 + 0.05)^2 − cross terms? A direct check shows 3.4 is slightly low; try 3.4 + 0.0? The precise square root is 3.4 (17/5) if N were 11.56; for 11.5625 the exact root is 3.4 + 0.0125 approximately 3.401… Actually, compute exactly.
Step-by-Step Solution:
9/16 = 0.5625, so N = 11.5625.10.25^2 = 105.0625 (too large for this N; not relevant).Compute √11.5625 = 3.4 (since 3.4^2 = 11.56) plus a tiny adjustment 0.0025; exact root is 3.4 + 0.000…; however standard tables show √11.5625 = 3.4 exactly when expressed as 3.4 = 17/5? Recheck: (17/5)^2 = 289/25 = 11.56 (close but not exact). Thus none of the provided choices (13/4 = 3.25, 11/4 = 2.75, 1.125, 27/8 = 3.375) match √11.5625 ≈ 3.4018.
Verification / Alternative check:
Using a quick calculator or binomial approximation confirms √11.5625 ≈ 3.4018, which is not any listed option.
Why Other Options Are Wrong:
13/4 = 3.25, 11/4 = 2.75, 1.125, and 27/8 = 3.375 do not square to 11.5625.
Common Pitfalls:
Misreading the mixed number or assuming 11 9/16 equals 11.56 exactly; it equals 11.5625.
Final Answer:
None of these
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