Answer: 0.0490
Explanation:
Given : Number of blue balls = 6
Number of yellow balls = 7
Total number of balls = 13
Total number of ways for selecting 4 balls from 13 balls :-

The number of ways of selecting 3 blue and one yellow :-

Now, the probability that of the balls selected, three of them will be blue and one of them will be yellow :-

Hence, the required probability is 0.0490 .