X ~ N(500,300)
pnorm(500,500,300) : 0.5
## [1] 0.5
pnorm(710,500,300) - pnorm(400,500,300): 0.388595
## [1] 0.388595
pnorm(450,500,300) - pnorm(330,500,300): 0.1483458
## [1] 0.1483458
Y ~ N(100,20)
pnorm(70,100,20) - pnorm(50,100,20): 0.06059754
## [1] 0.06059754
pnorm(110,100,20) - pnorm(105,100,20): 0.09275614
## [1] 0.09275614
pnorm(75,100,20,lower.tail = FALSE): 0.8943502
## [1] 0.8943502