estimation
- Thread starter 5455bull
- Start date
- Joined
- Apr 12, 2005
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- 11,339
It's a little too common a quesiton on GMAT, LSAT and various other entrance exams. I have yet to find a group of students who did not simply hate these problems.
Each one has various "solutions". The real trick to these problems is to get through them immediately. They are throw-aways that will increae your scores. If you waste ANY time on them, that will be time you will not be able to spend on worthwhile questions.
In this case, as in all such cases, give it a good look and then do SOMETHING that makes SOME sense. Do NOT worry about it.
My mind did this when presented with the problem statement:
"43.51 minus 13.54 is closest to what?"
I'm subtracting.
Both fractional parts are about 1/2, so I can just ignore that.
This leaves 43 - 13.
I can do that just by looking at it - 30.
If it's not quite a beautiful thing, I can repeat.
Both ones digits are '3', so subtraction takes care of that too.
This leaves 40 - 10.
I can do that just by looking at it - 30.
Do NOT memorize this "procedure". It is not likely to help you on any other problem, ever. You need to move quickly and make good decisions. That's what they are testing, anyway!
Each one has various "solutions". The real trick to these problems is to get through them immediately. They are throw-aways that will increae your scores. If you waste ANY time on them, that will be time you will not be able to spend on worthwhile questions.
In this case, as in all such cases, give it a good look and then do SOMETHING that makes SOME sense. Do NOT worry about it.
My mind did this when presented with the problem statement:
"43.51 minus 13.54 is closest to what?"
I'm subtracting.
Both fractional parts are about 1/2, so I can just ignore that.
This leaves 43 - 13.
I can do that just by looking at it - 30.
If it's not quite a beautiful thing, I can repeat.
Both ones digits are '3', so subtraction takes care of that too.
This leaves 40 - 10.
I can do that just by looking at it - 30.
Do NOT memorize this "procedure". It is not likely to help you on any other problem, ever. You need to move quickly and make good decisions. That's what they are testing, anyway!
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