Question

The purchasing director of a bank has just received a shipment of 100 printers. She has been told that the shipment includes 5 defective printers. She randomly selects two printers and tests them. If both printers work,the purchasing director accepts the shipment.
A)First find the probability that the two printers work.
B)Now use the idea of complements to find the probability that the shipment is rejected.

Answer 1

Since there is a 95% chance that you get two printers right, then you simply square the decimal equivalent which is .95 (Hence, you do .95^2). You will get .9025 (or 90.25%). 

For letter b, you simply subtract .9025 from 1. 
ans = 1-.9025
ans = .0975 (or 9.75%)

So the answer to B) would be there is a 9.75% chance the probability of a shipment can be rejected.