"the probability to buy a suite is 0.22

the probability to buy a shirt is 0.3

the probability to buy a tie is 0.28

the probability to buy a suite and shirt is 0.11

the probability to buy a suite and tie is 0.14

the probability to buy a tie and shirt is 0.28

what is the probability that the customer will not by anything?"

i was told that the probability that the customer will not by anything

equals the complement of the probability that he buys at least 1 item

why???

as i see it to solve it we need to do

not buy a shirt AND not buy a tie AND not buy suite=

(1-0.11)*(1-0.14)*(1-0.1)=0.68

why am i wrong?