Question

The weight of a soccer ball is normally distributed with a mean of 0.43 kg and a standard deviation of 0.01 kg.

Suppose 800 different soccer balls are in a warehouse.

About how many soccer balls weigh more than 0.45 kg?

Answer 1

any idea ?

Answer 2

how you think what mean a standard deviation of 0,01 kg ?

Answer 3

calculate the z-score for 0.45kg using 0.43kg as the mean and 0.01 kg as the standard deviation

convert the z-score to a percentile using a z-table or a calculator. now, the percentile tells you the percentage of weights that are **less* than 0.45 so you gotta take 100% - that percentile to get the percent of weights **above** 0.45

then multiply that by the number of items, 800