Drag z so that the shaded area under the standard normal curve, to the left of z, is 0.2643. Find z to two decimals.
Normal distribution worksheet with answers
Drag z so that the shaded area under the standard normal curve, to the left of z, is 0.9798. Find z to two decimals.
The exam scores are normally distributed with mean 65 points and standard deviation 10 points. What fraction lies between 45 and 70 points? Give P as a decimal.
The delivery times are normally distributed with mean 32 min and standard deviation 6 min. What fraction lies between 29 and 42.8 min? Give P as a decimal.
The IQ scores are normally distributed with mean 100 points and standard deviation 15 points. Find the value x below which 95% of them lie (the 95th percentile).
The heights of adult men are normally distributed with mean 178 cm and standard deviation 7 cm. Drag the cut-off so the shaded bottom 30% is to the left of it. Find the cut-off x.
Answer key
- 1. z = −0.63
- 2. z = 2.05
- 3. P = 0.6687
- 4. P = 0.6555
- 5. x = 124.7 points
- 6. x = 174.4 cm
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