ODD EVENS etc.

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ODD EVENS etc.

by thailandvc » Thu Jul 30, 2009 6:49 am
Anybody have a good way of approaching odd/evens/prime and inequalities problem?

I can do them but some of them can get pretty tedious. Most of them involve plug and check. I hate these. Not that they are hard, it just either uses the full 2 minutes or over, taking time away from other problems.

Just a general question for the plug and check type. Including number theory. Although these are better because you might be able to solve algebraically.

Thanks.

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Re: ODD EVENS etc.

by quant-master » Fri Jul 31, 2009 11:45 am
thailandvc wrote:Anybody have a good way of approaching odd/evens/prime and inequalities problem?

I can do them but some of them can get pretty tedious. Most of them involve plug and check. I hate these. Not that they are hard, it just either uses the full 2 minutes or over, taking time away from other problems.

Just a general question for the plug and check type. Including number theory. Although these are better because you might be able to solve algebraically.

Thanks.
Hi,

If you can post the specific problems I can help you out. As far as even/odd is concerned just remember these basic rules

even + or - even =even
odd + or - odd= even
even + or - odd=odd
even x even =even
even x odd = even
odd x odd = odd

Thanks,
Quant-Master
https://gmat-quants.blocked - My Blog Updated almost daily with new quant fundas. Find collection of quants question in my blog

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by thailandvc » Sat Aug 01, 2009 5:28 am
i don't really have a specific example because. i think all of them are "easy" if you have the time.

my question is really, how do people approach/simplify them? Or to state differently, what change did you make in approaching them when you got good at them?

Currently, they just take took much time for me and takes away from real hard problem like series/sequence recognition or tough geometry questions.

For example, the overlapping sets problem. It can be confusing to represent all the relationship via equations, but mgmat suggests making a the chart. that simplifies thing and limits mistake. Just wondering if there's anything like that for these plug/check type?

Thanks.