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Z-score and percentile

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The weight for a group of 18 month-0ld girls are normally distributed with a mean of 24.4 pounds and a standard deviation of 2.6 pounds. Use the table to find the percentage of 18 month-old girls who weigh more than 27.8 pounds.

z-score1. 0.1, 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
Percentile 53.98, 57.9, 61.8, 65.54, 69.15, 72.57, 75.8, 78.81,81.59, 84.1

z-score 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2
Percent 86.43, 88.5, 90.3, 91.92, 93.32, 94.52, 95.54, 96.41,97.13, 97.7

z-score 2.1 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3, 3.5, 4
Percent 98.21,98.6, 98.9, 99.18,99.38,99.53,99.65,99.74, 99.81, 99.9

what is the percentage of 18 month-old girls in the sample weigh more than 27.8 pounds?
(round all intermediate values to the nearest tenth as needed)

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This provides an example of using z-score and percentile to determine percentage.

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The weights for a group of 18 month-0ld girls are normally distributed with a mean of 24.4 pounds and a standard deviation of 2.6 pounds. Use the table to find the percentage of 18 month-old girls who weigh more than 27.8 pounds.
Z-score 1. 0.1, ...

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