There are 20 white hats and 13 black hats in a box. Neeraj randomaly took 3 hats (in succession) out

M4maths Previous Puzzles

12 Apr 2021 PROBABILITY

There are 20 white hats and 13 black hats in a box. Neeraj randomaly took 3 hats (in succession) out of the box and did not put them in the box. All three hats were black. What is the probability that the fourth hat that he takes out at random will also be black?

OPtion

1) 13/33
2) 10/33
3) 1/33
4) 1/30
5) 10/32
6) 1/3
7) 3/33
8) 12/33
9) 11/33
10) None of the above

Solution

Number of white hats = 20
Number of black hats = 13
Total avavilable hats = 33
After removing 3 black hats, number of black hats = 10
Now total available hats = 30
So the probability of took black hat = 10/30 = 1/3

Correct Option: 6 Best Solution (2)