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Question

Grabby Food Delivery has two computer systems, namely System A and System B available for processing online orders. All online orders can be processed by either one of the two systems. It is known that at any given time, System A has a 10% chance of being down (that is, not operational), while System B has a 25% chance of being down. The two computer systems operate independently. For a typical online order made, determine the probabilities that

(a) both systems are down (that is, not operational);

(b) both systems are operational;

(c) exactly one systems is operational; and

(d) online orders can be processed without delays.

Answer 1

(a) 0.10 x 0.25

(b) 0.90 x 0.75

(c) 0.10 x 0.75 + 0.90 x 0.25

(d) 1 - 0.10 x 0.25 [ at least 1 system is functional ]