Drag z so that the shaded area under the standard normal curve, to the left of z, is 0.9821. Find z to two decimals.
Normal distribution worksheet with answers
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The masses of boxes are independent and normal with mean 12 kg and standard deviation 0.8 kg. Find the probability P that the total mass of 16 of them exceeds 187.2 kg. Round z to two decimals.
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The battery lifetimes are normally distributed with mean 500 h and standard deviation 40 h. Drag the cut-off so the shaded bottom 95% is to the left of it. Find the cut-off x.
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Answer key
- 1. z = 2.1
- 2. P(X < x) = 0.5793
- 3. P = 0.9332
- 4. P = 0.7621
- 5. x = 566 h
- 6. x = 112.6 points
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