Question 1128035
this is a mean of 51 and a sd of 2
between 42 and 52 is a z=(xbar-mu)/std error
z=-9/2=-4.5
z=(1/2). Have a z between -4.5 and +0.5
probability is 0.6915
Greater than 51 has a probability of 0.5000
within 6 units is a z between -3 and +3, and that probability is 0.9973