Question

A box contains four tiles 1,4,5 and 8 as shown. Kelly chooses one time places it back in the box then chooses a second tile. What is the probability that the sum of the two chosen tiles is greater than 7?

Answer 1

Answer:

the answer to that question is 11/16

Answer 2

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.