Problem 5 · 1987 AJHSME
Easy
Geometry & Measurement
rectangle-area-decimals
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Answer: A — .088 m².
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Hint 1
Area is length × width — but both sides are less than 1, so before computing, ask: should the area be bigger or smaller than either side?
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Approach: multiply the sides, then place the decimal by estimating
- Area = 0.4 × 0.22. Multiply the digits: 4 × 22 = 88. Now place the point: 0.4 has one decimal place, 0.22 has two, so the product has three — 0.088 m².
- Sanity-check: multiplying two numbers below 1 always shrinks them, so the area must be smaller than 0.22. That instantly kills .62, .88 (a dropped decimal place), 1.24 (the perimeter, 2 × .4 + 2 × .22), and 4.22. Only 0.088 is smaller than both sides.
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