The plane will crash if and only if one of the following events will happen - (a) central and left engines fail - (b) central and right engines fail - (c) central and both left and right engines fail. The probabilities for each of these events are P(a) = 0.005*0.008*(1-0.008) = 0.00003968 P(b) = 0.005*0.008*(1-0.008) = 0.00003968 P(c) = 0.005*0.008*0.008 = 0.00000032 The probability of the crash is the sum P = P(a) + P(b) + P(c) = 0.00007968 (approximately). ANSWER