Question

The weights of steers in a herd are distributed normally. The variance is 10,000 10,000 and the mean steer weight is 1300lbs . Find the probability that the weight of a randomly selected steer is between 1169 and 1390lbs ⁢ lbs . Round your answer to four decimal places.

Answer 1

Solution :

Given that ,

mean = = 1300

standard deviation = = 10000=100

P(1169< x < 1390) = P[(1169-1300) /100 < (x - ) / < (1390-1300) / 100)]

= P( -1.31< Z < 0.9)

= P(Z < 0.9) - P(Z <-1.31 )

Using z table   

=0.8159-0.0951

probability= 0.7208