Question

Draw a density curve with appropriate shading and find the probabilities. Adult male Bengal tigers’ weights are normally distributed with a mean of 472 pounds and standard deviation of 26 pounds.

If a group of 12 adult male Bengal tigers are chosen, find the probability their mean weight is less than 498 pounds

Answer 1

Solution :

Given that,

mean = = 472

standard deviation = = 26

n = 12

= 472

=  / n = 26 / 12=7.5

P( < 498) = P[( - ) / < (498-472) / 7.5]

= P(z <3.47 )

Using z table  

=0.9997   

probability= 0.9997