mrs landes has a class of piano students with twice as many

mrs. landes has a class of piano students with twice as many girls as boys. of the boys, 90% practice regularly. if a student is selected at random. find the probability it is a boy who practice regularly.

Solution

Number of girls in the class n(g)= x,

Number of boys in the class n(b)=2 x

The probability boys practice =0.9

The probability it is a boy who practice regularly= Probability of selection boy * probability of boy practice

=(2/3)*0.9

=0.6