Difficulty: Easy
Correct Answer: 4312/3 cm3
Explanation:
Introduction / Context:
Given a sphere’s surface area, solve for its radius and then compute the volume. The numbers are chosen so that using π = 22/7 leads to exact integer simplification.
Given Data / Assumptions:
Concept / Approach:
From 4πr^2 = 616, obtain r first. Then substitute into V = (4/3)πr^3 and simplify exactly.
Step-by-Step Solution:
r^2 = 616/(4π) = 154/π = 154 * 7/22 = 49 ⇒ r = 7 cmV = (4/3)πr^3 = (4/3)π * 343 = (1372/3)πWith π = 22/7: V = (1372/3) * (22/7) = (196 * 22)/3 = 4312/3 cm3
Verification / Alternative check:
Decimal check: 4312/3 ≈ 1437.33 cm3, reasonable for r = 7 cm.
Why Other Options Are Wrong:
Other fractions do not match the exact cancellation with r = 7 and π = 22/7.
Common Pitfalls:
Using 616/π as if it were 616/3.14 with premature rounding; mis-evaluating r from S.
Final Answer:
4312/3 cm3
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