Question 1157477
z=(x-mean)/sd
z=(91-86)/5.2 =0.96 
prob z<0.96=0.83147 or 83.1%

more than 82 is z=(82-86)/5.2=-0.77
prob z>-0.77=0.7794 or 77.9%

between 80 and 89 is a z between -1.15 and +0.58
that probability is 0.5940 or 59.4%