Quant Strategies Flashcards
Always tackle percentages with 10s, 5s and 1s
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Round as much as possible.
When rounding mark whether you’ve rounded up or down to guide answer selection
Strategy
If multiplying by 5, multiply by 10 and divide by 2.
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If dividing by 5, divide by 10 and multiply by 2
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To multiply by 9, multiply by 10 and then subtract the number
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If you see x>1000 it probably means ignore any small addition or subtraction next to it
Knowing q^2 = r^2 does not tell you that q=r
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How many equations do you need to solve for n variables?
N
For data sufficiency with exponents pick numbers in zones: less than -1, between -1-0, 0-1, 1+
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GMAT doesn’t usually allow roots in the denominator of a fraction. You need to simplify by multiplying by 1.
You shouldn’t have to multiply by pi for anything on the GMAT. If you do, approximate with 3.
If a number is increased by 10% and then decreased by 10% is it bigger or smaller than the original value?
Smaller.
5^4
625
4^4
256
2^3 * 5^3
10^3
