P/S need help...

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metropia
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Topic: P/S need help...
PostMon Mar 26, 2007 3:52 pm
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Four extra-large sandwiches of exactly the same size were ordered for m students, where m > 4. Three of the sandwiches were evenly divided among the students. Since 4 students did not want any of the fourth sandwich, it was evenly divided among the remaining students. If Carol ate one piece from each of the four sandwiches, the amount of sandwich that she ate would be what fraction of a whole extra-large sandwich?


A. m+4/m(m-4) B. 2m-4/m(m-4) C.4m-4/m(m-4) D. 4m-8/m(m-4)
E. 4m-12/m(m-4)


I tried to plug in the number (assume that m=12) ...can't get the right answer.
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jayhawk2001
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PostMon Mar 26, 2007 8:01 pm
First 3 sandwiches divided amongst m people, so each person gets 3/m
of the sandwich.

Last sandwich divided among m-4. So each person gets 1/(m-4)

So carol eats 3/m + 1/(m-4) = (4m-12) / (m(m-4))
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Cybermusings
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PostWed Mar 28, 2007 7:38 am
Four extra-large sandwiches of exactly the same size were ordered for m students, where m > 4. Three of the sandwiches were evenly divided among the students. Since 4 students did not want any of the fourth sandwich, it was evenly divided among the remaining students. If Carol ate one piece from each of the four sandwiches, the amount of sandwich that she ate would be what fraction of a whole extra-large sandwich?


A. m+4/m(m-4)
B. 2m-4/m(m-4)
C.4m-4/m(m-4)
D. 4m-8/m(m-4)
E. 4m-12/m(m-4)


This one seems easy...Lets hope I get it right

First 3 sandwiches divided amongst m students

Thus each student gets 3/m sandwich

Last sandwich divided amongst m - 4 students

Therefore each of those m-4 students gets 1/m-4 sandwich

Carol ate 3/m + 1/m-4 sandwich

= (3(m-4)+m)/m(m-4)

= 3m - 12 + m / m (m - 4)

= 4m - 12 / m (m - 4)

Hence E
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