Hello,
Can you please tell me if my solution is correct here:
A teacher will pick a group of 5 students out of a group of 5 girls and 5 boys, what
is the probability of picking a group that includes exactly 3 girls?
(This is from GMAT Word Problems book. The answer in the book seems to be wrong.)
My approach is as follows:
P(GGGBB) = (5/10)(4/9)(3/8)(5/7)(4/6)= 5/126
Now we can find the total number of ways to arrange 3 girls and 2 boys using Brent's MISSISSIPPI technique (which Brent has also explained in detail here: https://www.beatthegmat.com/p-c-t274535.html#712266 ):
(5 x 4 x 3 x 2 x 1)/(3! x 2!) = 10
Hence, total number of ways to pick 3 girls and 2 boys = (5/126)(10) = 25/63
Thanks a lot,
Sri
Can you please tell me if my solution is correct here:
A teacher will pick a group of 5 students out of a group of 5 girls and 5 boys, what
is the probability of picking a group that includes exactly 3 girls?
(This is from GMAT Word Problems book. The answer in the book seems to be wrong.)
My approach is as follows:
P(GGGBB) = (5/10)(4/9)(3/8)(5/7)(4/6)= 5/126
Now we can find the total number of ways to arrange 3 girls and 2 boys using Brent's MISSISSIPPI technique (which Brent has also explained in detail here: https://www.beatthegmat.com/p-c-t274535.html#712266 ):
(5 x 4 x 3 x 2 x 1)/(3! x 2!) = 10
Hence, total number of ways to pick 3 girls and 2 boys = (5/126)(10) = 25/63
Thanks a lot,
Sri
