SOLUTION: A teacher has a class consisting of 8 BOYS and 4 GIRLS. How many groups of 5 can he make if: -in every group there should be AT LEAST 1 girl?.. Thanks so much in advance. I'm

Algebra.Com
Question 409323: A teacher has a class consisting of 8 BOYS and 4 GIRLS. How many groups of 5 can he make if:
-in every group there should be AT LEAST 1 girl?..
Thanks so much in advance. I'm not really sure how to solve for this... ^_^ God Bless
please send me the answer ASAP! :D it's our assignment thank you!

Found 2 solutions by stanbon, sudhanshu_kmr:
Answer by stanbon(75887)   (Show Source): You can put this solution on YOUR website!
A teacher has a class consisting of 8 BOYS and 4 GIRLS. How many groups of 5 can he make if:
-in every group there should be AT LEAST 1 girl?..
-------
P(at least one) = 1 - P(no girls)
---
P(no girls) = 8C5/12C5 = 0.071
--
P(at least one girl) = 1-0.071 = 0.929..
============
Cheers,
Stan H.

Answer by sudhanshu_kmr(1152)   (Show Source): You can put this solution on YOUR website!

No. of ways to form group of 5 from total 12 students= 12C5 (no restriction)

no. of ways to form group of 5 from 8 boys DISABLED_event_only= 8C5 ........ ( no girl )

now, we subtract it from total possible no.

no. of ways to form group in which at least 1 girl = 12C5 - 8C5

= 792 - 56 = 736


RELATED QUESTIONS

There are 6 boys and 4 girls and a group of 5 people must be formed. How many groups are... (answered by edjones)
A class consists of 15 students. The instructor wants to pick a group of 4 to work on a... (answered by sudhanshu_kmr)
There are 6 boys and 18 girls in a class. A group of 5 students is needed to work on a... (answered by Edwin McCravy)
A teacher has 7 boys and 11 girls in her class. In how many ways can she select 8 of the... (answered by stanbon)
A teacher has 18 boys and 11 girls in her class. In how many ways can she select 8 of the (answered by Timnewman)
The ratio of boys to girls in a graduating class is 4 to 5. How many boys and girls are... (answered by Fombitz,lenny460)
There are 6 boys and 4 girls and a group of 5 people must be formed. How many groups are... (answered by Theo)
At the end of each week, a generous teacher gives some candy to a few randomly selected... (answered by ikleyn)
A teacher has 10 boys and 12 girls in her grade school class. In how many ways can she... (answered by sudhanshu_kmr)