Difficulty: Medium
Correct Answer: 12
Explanation:
Introduction / Context:We match a left-hand expression to a percentage of a number. One term involves scientific notation. After computing both sides approximately, we solve for the missing addend and select the nearest integer option.Given Data / Assumptions:
Concept / Approach:Evaluate the fixed product first, then the right-hand side, and finally isolate the unknown ?. Round to the nearest feasible option as customary for approximation problems.Step-by-Step Solution:
0.0005 × 10^3 = 0.5.0.5 × 76 = 38.Right side: 1.7 × 29.98 ≈ 50.966 (≈ 51).So 38 + ? ≈ 50.966 ⇒ ? ≈ 12.966.Nearest option: 12 (among 12, 15, 16, 18).Verification / Alternative check:If we round 29.98 to 30, RHS ≈ 51 exactly; then ? ≈ 13. The closest available integer is still 12 (off by 1), which is acceptable within approximation tolerance given the choices provided.Why Other Options Are Wrong:
Common Pitfalls:Misinterpreting 10^3 or distributing 0.0005 incorrectly. Always compute the power-of-ten part first to stabilize place values, then multiply the remaining factors.Final Answer:
12
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