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Source: Beat The GMAT — Problem Solving |
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dally_gmat
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What is OA?
v_shiv wrote:7 males and 7 females. for each male, there can be 6 possible partners. 7*6 = 42. So, the answer is 42
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dally_gmat
- Senior | Next Rank: 100 Posts
- Posts: 31
- Joined: Mon Sep 15, 2008 6:16 pm
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I may be wrong ..but heres what I think :
Total no of ways of selecting two teams for mixed double (2 Men. 2 Women):
2 M = 7*6
2G : 7*6
Total no of ways : 42*42 -----(A)
No of ways so that couple always play together = no of ways selecting 2 couples from 7 = 7*6 = 42------(B)
No of ways so that couple dont play together in a set = A-B = 42*42-42
= 42*41
Total no of ways of selecting two teams for mixed double (2 Men. 2 Women):
2 M = 7*6
2G : 7*6
Total no of ways : 42*42 -----(A)
No of ways so that couple always play together = no of ways selecting 2 couples from 7 = 7*6 = 42------(B)
No of ways so that couple dont play together in a set = A-B = 42*42-42
= 42*41
dally_gmat wrote:What is OA?
v_shiv wrote:7 males and 7 females. for each male, there can be 6 possible partners. 7*6 = 42. So, the answer is 42
