Given : μ = 5634.5 σ = 642
n = 100
P(5600 < x' < 5700)
= P((5600 - 5634.5) / 642 * √100 < x' < (5700 - 5634.5) / 642 * √100)
= P(-0.5374 < x' < 1.0202)
= P(x' < 1.0202) - P(x' < -0.5374)
Using z tables,
= 0.8462 - 0.2955
= 0.5507.
The average mass of a freight car is 5634.5 kg with a standard deviation of 642...
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