Ratio of members

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Ratio of members

by vishubn » Fri Oct 03, 2008 5:31 am
A certain club has 20 members. What is the ratio of the member of 5-member
committees that can be formed from the members of the club to the number of 4-member
committees that can be formed from the members of the club?
A. 16 to 1
B. 15 to 1
C. 16 to 5
D. 15 to 6
E. 5 to 4

Vishu !

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by krazy800 » Fri Oct 03, 2008 6:12 am
Is it C?
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by vivek.kapoor83 » Fri Oct 03, 2008 6:20 am
5 member committee can be formed -

P1 P2 P3 P4 P5
20*19*18*17*16


Similarly 4 member committee - 20*19*18*17
Dividing - So it should be 16:1.
OA Pls

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by vishubn » Fri Oct 03, 2008 6:40 am
hi Vivek even i ended up in A

but OA is C

Can anyone explain this ??

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by krazy800 » Fri Oct 03, 2008 7:33 am
Simple It is

The number of 5 member committees that can be formed = 20C5
The number of 4 member committees that can be formed = 20C4


(20C5/20C4)=16:5
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by stop@800 » Fri Oct 03, 2008 2:20 pm
as order does not matters
so combination....

20C5 / 20C4