Question 1161601
z=(x-mean)/sd
z=(15-10.15)/2.45=1.978
probability z> 1.978 is 0.0239
between 12 and 14 
do it the same way or on calculator 2nd VARS2 normal cdf ENTER (12,14,10.15,2.45)ENTER
0.1671
it is probability z is between 0.755 and 1.571 (0.1670), the difference in the last decimal place was that I was rounding in the second.