After winning 80 percent of the first 40 matches he played, Igby won 50 percent of his remaining matches. How many total matches did he win?
(1) If Igby had won 50 percent of the total number of matches he played, he would have lost 12 more total matches.
(2) If Igby had won 80 percent of the total number of matches he played, he would have won 18 more total matches.
OA is B
Igby's Scorecard
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- hja379
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Last edited by hja379 on Mon Mar 21, 2011 7:59 am, edited 1 time in total.
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interesting DS, thanks for posting
st(1) offers conditional losses while we have no restriction per win/loose Only, what if draw -Not Sufficient;
st(2) Sufficient, as 0.8*40 + 0.5x +18 = 0.8*40 + 0.8x and we solve for x original wins ...
0.3x=18, x=60
st(1) offers conditional losses while we have no restriction per win/loose Only, what if draw -Not Sufficient;
st(2) Sufficient, as 0.8*40 + 0.5x +18 = 0.8*40 + 0.8x and we solve for x original wins ...
0.3x=18, x=60
hja379 wrote:After winning 80 percent of the first 40 matches he played, Igby won 50 percent of his remaining matches. How many total matches did he win?
(1) If Igby had won 50 percent of the total number of matches he played, he would have lost 12 more total matches.
(2) If Igby had won 80 percent of the total number of matches he played, he would have won 18 more total matches.
OA after discussion.
Last edited by Night reader on Mon Mar 21, 2011 3:31 pm, edited 2 times in total.
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- hja379
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I've updated the OA. It is not E.Night reader wrote:interesting DS, thanks for posting
st(1) offers conditional losses while we have no restriction per win/loose Only, what if draw -Not Sufficient;
st(2) is Not Sufficient, as 0.8*40 + 0.5x = 0.2*40 + 0.5x + 18 and we solve for x original wins ...
0.5x are canceled LHS-RHS - we are left with no variables
Combined st(1&2): conditionally 12 more losses and 18 more wins; since we don't know how many games Igby has lost Not Sufficient
IOM E
hja379 wrote:After winning 80 percent of the first 40 matches he played, Igby won 50 percent of his remaining matches. How many total matches did he win?
(1) If Igby had won 50 percent of the total number of matches he played, he would have lost 12 more total matches.
(2) If Igby had won 80 percent of the total number of matches he played, he would have won 18 more total matches.
OA after discussion.
Google "GMAT Pill"<--really helpful, worth checking out--especially for RC passages.
e-gmat SC: Never thought it would be fun learning SC.
India School Fund: Education through Innovation - A HBS start-up.
e-gmat SC: Never thought it would be fun learning SC.
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very tricky problem to me, initially i got D, but then found my mistake
let it be x the number of remaining games, so he win in total
0,8*40+0,5*x=32+0,5x
he lost in total 0,2*40+0,5x=8+0,5x
and the total number of all games he played=40+x, clearly we need to find x, after that we can find everything
(1) 0,5*(40+x)-If Igby had won 50 percent of the total number of matches he played
(8+0,5x+12)=20+0,5x-he would have lost 12 more total matches.
and in total he played 40+x games
win+lost=total, (20+0,5x)+(20+0,5x)=40+x, we already have this info from this we got that 40+x=40+x, no way to find the value of x, insuff
(2)
0,8(40+x)=32+0,8x-If Igby had won 80 percent of the total number of matches he played
(32+0,5x)+18- he would have won 18 more total matches.
32+0,8x=50+0,5x, 0,3x=18, x=60. total number if winning games =32+0,5*60=32+30=62 suff
let it be x the number of remaining games, so he win in total
0,8*40+0,5*x=32+0,5x
he lost in total 0,2*40+0,5x=8+0,5x
and the total number of all games he played=40+x, clearly we need to find x, after that we can find everything
(1) 0,5*(40+x)-If Igby had won 50 percent of the total number of matches he played
(8+0,5x+12)=20+0,5x-he would have lost 12 more total matches.
and in total he played 40+x games
win+lost=total, (20+0,5x)+(20+0,5x)=40+x, we already have this info from this we got that 40+x=40+x, no way to find the value of x, insuff
(2)
0,8(40+x)=32+0,8x-If Igby had won 80 percent of the total number of matches he played
(32+0,5x)+18- he would have won 18 more total matches.
32+0,8x=50+0,5x, 0,3x=18, x=60. total number if winning games =32+0,5*60=32+30=62 suff
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@clock, is not that we make assumption here about no draws in matches/games in D st(1)? what's the source?
initially, i put 0.5x on both sides, i don't why - but now i see the variables are not canceled and it's solvable for x=60
answer would be 60/2+32=62 games?
initially, i put 0.5x on both sides, i don't why - but now i see the variables are not canceled and it's solvable for x=60
answer would be 60/2+32=62 games?
My knowledge frontiers came to evolve the GMATPill's methods - the credited study means to boost the Verbal competence. I really like their videos, especially for RC, CR and SC. You do check their study methods at https://www.gmatpill.com