Question 1157814
z=(x-mean)/sd
(2.58-2.5)/0.02 is +4
probability of z<4 is 1.0 to four decimal places.

between 2.54 and 2.58 will be the probability z is between 2 and 4
 go to 2nd VARS 2 for normalcdf (you almost never want normalpdf)
enter 2,4
hit enter'
0.0228 is the probability.