Drag z so that the shaded area under the standard normal curve, to the left of z, is 0.3372. 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 0.9884. Find z to two decimals.
The IQ scores are normally distributed with mean 100 points and standard deviation 15 points. What fraction lies between 100 and 118.75 points? Give P as a decimal.
Drag z so that the shaded area under the standard normal curve, to the right of z, is 0.8508. Find z to two decimals.
The exam scores are normally distributed with mean 65 points and standard deviation 10 points. Drag the cut-off so the shaded bottom 10% is to the left of it. Find the cut-off x.
Runner A's lap time X and runner B's lap time Y are independent and normal: X has mean 52 s and standard deviation 4 s, Y has mean 48 s and standard deviation 3 s. Find the probability P that X is greater than Y. Round z to two decimals.
Answer key
- 1. z = −0.42
- 2. z = 2.27
- 3. P = 0.3944
- 4. z = −1.04
- 5. x = 52.2 points
- 6. P = 0.7881
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