Question

A particular fruit's weights are normally distributed, with a mean of 660 grams and a standard deviation of 18 grams.

If you pick one fruit at random, what is the probability that it will weigh between 615 grams and 712 grams.

Answer 1

Solution :

Given that ,

mean = = 660

standard deviation = =18

P(615< x <712 ) = P[(615 - 660) / 18< (x - ) / < (712 - 660) / 18)]

= P( -2.5< Z < 2.89)

= P(Z <2.89 ) - P(Z < -2.5)

Using z table   

=  0.9981 - 0.0062

probability= 0.9919