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Committee Choice Concern (Posted on 2010-05-17)

A committee of 5 is to be chosen from a group of 9 people.

Determine the total number of ways this can be accomplished, given that:

(i) Harold and Warren must serve together or not at all, and:

(ii) Lucy and Deanna refuse to serve with each other.

See The Solution Submitted by K Sengupta

Rating: 5.0000 (1 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)

just counting

| Comment 1 of 3

Answer: 30

SOLUTION:

CASE 1: HWL, notD We have 3 in and select another 2 out of 5 i.e. 10

CASE 1' HWD, notL .... same thing

Case 2 L, notD &not HW 4 needed out of 5 i.e. 5

Case 2' D, notL &not HW ..... same thing

2*10+2*5=30

oops! Without both ladies:

Two more cases, in addition to Ady's:

Case 3: HW, not D or L: select another 3 out of 5, ie 10

Case 3': Not HW, not D or L: select 5 out of 5, equal 1

So, previous 30, + 10 + 1 = 41

The correct answer: 41

Edited on May 17, 2010, 5:14 pm

Posted by Ady TZIDON on 2010-05-17 14:13:17

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