# Normal Distribution and Birth Weights

A researcher recorded the birth weights of a sample of newborn babies. The average birth weight was 7.2 pounds and the standard deviation was 0.9 pound. The birth weights follow a normal distribution.

1. Label the number line so that the curve is a normal curve and follows the properties of the normal distribution. Include 3 standard deviations above and below the mean.

2. Determine the percent of newborns that weight between 2 standard deviations below the mean and 2 standard deviations above the mean.

3. Determine the percent of newborns that weight less than the mean.

4. Determine the percent of newborns that weight between 1 standard deviation above the mean and 3 standard deviations above the mean.

5. Approximately what percent of newborns weighed between 4.5 pounds and 9.9 pounds?

6. Approximately what percent of newborns weight more than 9 pounds?

7. Approximately what percent of newborns weighed less than 6.3 pounds?