GMAT Club Legend
Joined: 05 Apr 2006
Affiliations: HHonors Diamond, BGS Honor Society
Posts: 5916
Given Kudos: 7
Schools: Chicago (Booth) - Class of 2009
WE:Business Development (Consumer Products)
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07 May 2006, 19:28
I'm ok with word problems...
The mistakes I tend to make are truly the careless. Stuff like 9*6 and I think 36 for some crazy reason. Or x - 3 < 7 ... and I think minus 3 and get x < 4 .... its just a question of forcing myself to slow down and think for a second extra.
A lot of people I know make these kinds of mistakes. I did some practice problems with a friend today and he did 10 + 4 = 16. Obviously wrong. I did 5+6+4+3 = 17. Also obviously wrong. Going too fast, making silly mistakes.
I've just forced myself to slow down whenever I see basic math - its stupid to get a combined rate problem wrong after you set up all the stuff correctly because you made some stupid error.
I've also forced myself to look for the clean solutions. Almost every problem I see, there's some clean solution.
zx - yz equals what
(a) x - y = 2
(b) z = 3
could sit there and plug in stuff, or just realize z(x-y) is xz-yz ... bad example I guess.
Or something like
x is one of the following: 1/4, 2/5, 3/8
what is X?
(1) 1/2 < x < 7/8
(2) 1/9 < x < 7/12
Bad solution: find the common demon... (by the way I made the above up, so dont try to solve it per se, it may not be congruent)
Quick solution: realize that 3/8 is less than 7/8, 1/4 is less tahn 1/2, and then check out 2/5 and 7/8 --- 16 vs 35. Ditto for 2.
They are both bad examples...
but i think anyone who's been studying knows what I mean.
Stuff like...
10,000 invested 8% conpounded twice annually for a period of 1 year ... equals how much?
Whats faster?
10,000*1.04 = something * 1.04 = your answer?
P*(1 + r/n)^nt
10,000*(1 + .08/2)^nt
Becoming faster at mutiplying decimals with greater confidence - reduce risk of misplaced decimal place.
1.04 * 1.04
104 * 104
move decimal 4 places. answer.
Working with fractions quicker:
which is greater: 25/3 + 19/6 + 98/24
or 5/12 + 87/36 + 75/12
arrange in order... either find a common denominator and sit there and solve... or multiply out by 12 ... much faster!
you get the idea.