Approximate (nearest sensible option): 16.003 × 27.998 − 209.010 = ?

Difficulty: Easy

Correct Answer: 240

Explanation:

Introduction: Mixed multiply–subtract approximations are best handled by rounding each factor to a nearby integer and then performing the operations. Because the options are broad, nearest-integer rounding typically yields the correct choice.

Given Data / Assumptions:

  • Expression: 16.003 × 27.998 − 209.010
  • Options are spaced tens apart, so integer rounding is adequate.

Concept / Approach: Approximate 16.003 ≈ 16, 27.998 ≈ 28, 209.010 ≈ 209. Compute product then subtract, comparing to options. Sensitivity is low because decimal tails are tiny relative to magnitudes here.

Step-by-Step Solution:

16 × 28 = 448 448 − 209 ≈ 239 Nearest sensible option ≈ 240

Verification / Alternative check: Using slightly finer rounding (e.g., 16 × 28 − 209.01) still centers near 239, confirming 240 is the closest listed value.

Why Other Options Are Wrong: 150 and 200 are far too small; 75 is not plausible; 260 overshoots the refined estimate by about 20+.

Common Pitfalls: Rounding 27.998 to 27 (down) would bias low; standard practice is to round to nearest integer (28).

Final Answer: 240

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