From here, divide both sides by 3^(-8), and you're left with (1+3+9+27)/4 = x, or x = 10.
This works on all sorts of factoring problems on the GMAT, so it's a great technique.
I need help with a complicated power problem
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Matt@VeritasPrep
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I usually start by factoring out the smallest power of the common base that's been added (click the image, for some reason it got cut down):
From here, divide both sides by 3^(-8), and you're left with (1+3+9+27)/4 = x, or x = 10.
This works on all sorts of factoring problems on the GMAT, so it's a great technique.
From here, divide both sides by 3^(-8), and you're left with (1+3+9+27)/4 = x, or x = 10.
This works on all sorts of factoring problems on the GMAT, so it's a great technique.
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GMATGuruNY
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Strategy: Factor out the MOST NEGATIVE EXPONENT.If (3ˉ� + 3ˉ� + 3ˉ� + 3ˉ�)/4 = x * 3ˉ�, what is the value of x?
Factor out 3ˉ�:
3ˉ� (1 + 3 + 3² + 3³) / 4 = x * 3ˉ�
Cancel out 3ˉ� and simplify:
(1 + 3 + 9 + 27)/4 = x
40/4 = x
10 = x.
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Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
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Student Review #3
