Guest

In how many ways 7 persons can be selected from 5 indian, 4 british and 2 chinise, if atleast 2 are to be selected from each country.

In how many ways 7 persons can be selected from 5 indian, 4 british and 2 chinise, if atleast 2 are to be selected from each country.

Grade:11

2 Answers

Puneet Mittal AskiitiansExpert-IITD
22 Points
13 years ago

Hi Rajat,

The answer is :

At least 2 persons have to be slected form each country so :

ways of selecting 2 persons from 5 indians is 5C2

ways of selecting 2 persons from 4 british is 4C2

ways of selecting 2 persons from 2 chinese is 2C2 

Thus ways of slecting 6 persons form entire group is   5C2 * 4C2 * 2C2 

Now 1 person has to be selected from remaing 3 Indians and 2 british and 0 chinese

possible way of selceting 1 person is 5C1

Thus final answer to select 7 persons is 5C2 * 4C2 * 2C2 *  5C1

Please feel free to ask as many questions you have.

Puneet

 

Rajat Goel
31 Points
13 years ago

hey I have answer booklet (not solution). And in it answer given is "100".

 

My one frnd has suggested me the solution as:

you have to choose two chinese forced, at least two british and two indians, and one between british or indian. so you have

1*4C2*4C2*(3+2)=180    the last term: 3 indians+2 british....

 

But its also wrong

Think You Can Provide A Better Answer ?

ASK QUESTION

Get your questions answered by the expert for free