There are a total of
95 + 51 + 71 + 82 + 89 + 80 = 468
customers.
a) There are 51 + 71 + 82 + 89 = 293
customers that satisfy the given condition,
so the probability is 293/468 = 0.6261
b) There are 95 + 51 + 71 + 80 = 297
customers that satisfy the given condition,
so the probability is 297/468 = 0.6346
c) There are 89 + 80 = 169
customers that satisfy the given condition,
so the probability is 169/468 = 0.3611