Hi Distribution: normal with µ = 120 and σ = 20 Using TI or similarly an inexpensive calculator like an Casio fx-115 ES plus SELECT ONE: P( 100 < x < 130) = normalcdf(100,130,120,20) = .5328 P( x > 75) = normalcdf(75,9999,120,20) = .9878 Wish You the Best in your Studies.