Question

Weights of cars passing over Bridge part 3
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Answer 1

d. 30.42%

Explanation:

A suitable calculator pegs the probability of exceeding 0.51724 standard deviations above the mean as about 0.3025 = 30.25%. The closest answer is choice D.

Z = (X -μ)/σ = (4000 -3550)/870 = 450/870 ≈ 0.51724

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Comment on the answer choices

30.42% is the probability of exceeding 3995 pounds, not 4000.