Drag z so that the shaded area under the standard normal curve, to the left of z, is 0.0409. 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 0.1093. Find z to two decimals.
The exam scores are normally distributed with mean 65 points and standard deviation 10 points. What fraction lies between 65.5 and 85 points? Give P as a decimal.
Drag z so that the shaded area between −z and z under the standard normal curve is 0.4713. Find z to two decimals.
The bag weights are normally distributed with mean 250 g and standard deviation 5 g. Drag the cut-off so the shaded top 15% is to the right of it. Find the cut-off x.
The battery lifetimes are normally distributed with mean 500 h and standard deviation 40 h. Find the value x below which 20% of them lie (the 20th percentile).
Answer key
- 1. z = −1.74
- 2. z = −1.23
- 3. P = 0.4573
- 4. z = 0.63
- 5. x = 255.2 g
- 6. x = 466.3 h
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