Question 1152127
<br>
The opposite of "at least one of the two is happy" is "both are unhappy".<br>
The probability that both are unhappy is (0.2)(0.2) = 0.04; so the probability that at least one is happy is 1-0.04 = 0.96.<br>
An alternative method for calculating the probability....<br>
P(both happy) = (0.8)(0.8) = 0.64
P(A happy, B not happy) = (0.8)(0.2) = 0.16
P(A not happy, B happy) = (0.2)(0.8) = 0.16<br>
P(at least one happy) = 0.64+0.16+0.16 = 0.96<br>