00:01
Hi, from the question given that a bag contains x counter, x counter in a bag.
00:19
Now there are only red counter and blue counter in the bag.
00:24
So here b represents the blue counter and r represents the red counter.
00:37
So the bag contains only the red and blue counter.
00:40
So that means that b plus r is equal to x.
00:47
Since a bag contains blue counters, then red counters in a bag.
00:51
So here blue counter is equal to 4 plus r.
00:57
So b minus r is equal to 4.
01:02
So here 20 takes at random 2 counters from the bag.
01:08
The probability that it takes 2 blue counters from the bag is 3 by 8.
01:14
So probability of taking blue counter first, first chance.
01:25
So there will be a 4 plus r blue counter.
01:32
So 4 plus r blue counter out of we have in a bag contains x counters.
01:39
And similarly probability of taking blue counter in the second chance also.
01:45
So that is equal to 4 plus r minus 1 since already we have taken 1 divided by x minus 1.
01:56
Now the probability of taking 2 blue counters will be equal to 3 by 8.
02:02
So 4 plus r divided by x multiplied with 4 plus r minus 1 divided by x minus 1 is equal to 3 by 8.
02:14
Now here 4 plus r divided by 8, sorry divided by x multiplied with 4 minus 1 is 3, 3 plus r divided by x minus 1 which is equal to 3 by 8.
02:32
So from this equation we need to obtain the value of 4 plus r.
02:39
So from this 4 plus r plus r is equal to x...