Question 936153
P(x <.09) = P(z < -.01/sqrt(.10*.90/100))
P(.09 < x < .10) = .5 - P(z < .09) = .5 - normalcdf(-100, -1/3)
.....
P( x <.12) = P(z< .02/sqrt(.10*.90/100)) = normalcdf(-100, 2/3)