The delivery times are normally distributed with mean 32 min and standard deviation 6 min. What fraction is above 44 min? Find P(X > x) as a decimal.
Normal distribution worksheet with answers
Drag z so that the shaded area under the standard normal curve, to the left of z, is 0.3707. Find z to two decimals.
The IQ scores are normally distributed with mean 100 points and standard deviation 15 points. What fraction lies between 82.75 and 108.25 points? Give P as a decimal.
The IQ scores are normally distributed with mean 100 points and standard deviation 15 points. What fraction lies between 88.75 and 112.75 points? Give P as a decimal.
The battery lifetimes are normally distributed with mean 500 h and standard deviation 40 h. Drag the cut-off so the shaded bottom 40% is to the left of it. Find the cut-off x.
The IQ scores are normally distributed with mean 100 points and standard deviation 15 points. Drag the cut-off so the shaded bottom 80% is to the left of it. Find the cut-off x.
Answer key
- 1. P(X > x) = 0.02275
- 2. z = −0.33
- 3. P = 0.5838
- 4. P = 0.5757
- 5. x = 490 h
- 6. x = 112.6 points
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