Question

A grocery store will only accept yellow onions that are at least 2.75 in. In diameter. A grower has a crop of onions with diameters that are normally distributed, with a mean diameter of 2.5 in. And a standard deviation of 0.25 in. What percent of the onions will be accepted by the grocery store?

Answer 1

Explanation:

Calculate z-score firstly

z-score = (x-mean)/SD = (2.75-2.5)/0.25 = 0.25/0.25 = 1

P( x greater than or equal to 2.75) = P(z greater than or equal to 1)

= 1 - p(z <1)

P(z<1) from table = 0.84134

1-p(z<1) = 0.15866 or 15.866%