WA@jit2975
Hey anyone who watched the recent Probability lecture from Aditya?
I have a doubt.
Would love to discuss.
Please ping
I am solving this question, using the Permutation method taught by Aditya but my answer in 2 of them seems to be double of the actual answer. I am not sure what mistake I am making.
There are 5 different coloured balls in a bag. A ball is chosen and replaced 4 times. What is the probability that:
a) all the balls chosen are different colours?
b) 2 of the balls are the same colour and other 2 are of different color each?
c) 2 of the balls are the same colour and other 2 are of different color each?
d) 3 of the balls are the same colour?
Assuming we have balls of colors A,B,C,D and E
a) P(ABCD)= (5/5)x(4/5)x(3/5)x(2/5) = 24/125 ✅
b) P(AABC) = (5/5)x(1/5)x(4/5)x(3/5)x4!/2! = 144/125 ❌. Answer is half of this i.e. 72/125
c) P(AABB) = (5/5)x(1/5)x(4/5)x(1/5)x4!/2!/2! = 24/125 ❌. Answer is half of this i.e. 12/125
d) P(AAAB) = (5/5)x(1/5)x(1/5)x(4/5)x4!/3! = 4!/3! ✅
Reference to the video:
https://www.youtube.com/watch?v=cUjI2V5 ... LL&index=6