Answer:
The probability that the sum of the two chosen tiles is greater than 7 is 3/8
Step-by-step explanation:
The probability that the sum of the two chosen tiles is greater than 7 is the probability that he chooses either;
4 and 5
8 and 1
8 and 4
4 and 4
5 and 5
8 and 8
The probability of choosing a one tile out of 1, 4, 5, or 8 with replacement = 1/4
The probability of choosing the tiles such that a particular tile is chosen followed by another particular tile is the product of both probabilities, which gives;
The probability of choosing 4 and 5 = 1/4 × 1/4 = 1/16
Similarly the probability of choosing 8 and 1 = 1/16
Which gives, the probability of choosing either 4 and 5, 8 and 1, 8 and 4, 4 and 4, 5 and 5, and 8 and 8 is therefore;
(1/4 × 1/4) × 6 = 3/8
Which gives;
The probability that the sum of the two chosen tiles is greater than 7 = 3/8.
