52 A system consists of two identical pumps 1 and 2 If one pump fails the system will still operate However because of the added strain the remaining pump is now more likely to fail than was originally the case That is r P 2 fails 1 fails P 2 fails q If at least one pump fails by the end of the pump design life in 7 of all systems and both pumps fail during that period in only 1 what is the probability that pump 1 will fail during the pump design life