Hi Jheisra,
What is the source of this question? Is it from a GMAT source or a 'math book?' I ask because the wording is clunky and you have not included the 5 answer choices. The math is based on Quadratic Algebra, so there are actually 2 solutions. As it stands, having those 5 answers would make solving this question REALLY easy. Without them though, we're almost forced to take a 'math heavy' approach.
With the information that we've been given, we can form the following equation (we can refer to the numbers as X and 3X):
(X)(3X) = (X+3X) + 55
3X^2 = 4X + 55
From here, we can solve Algebraically or use 'brute force' (and if we had 5 answer choices, then we could TEST THE ANSWERS).
Algebraically:
3X^2 - 4X - 55 = 0
(X - 5)(3X + 11) = 0
X = 5 or - 11/3
GMAT assassins aren't born, they're made,
Rich
Help me please.
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Do we mean an actual math book, or a phony math book? Seems like real math to me, no quotations required.[email protected] wrote:a 'math book?'
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Matt@VeritasPrep
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We've got
a = 3b
and
a*b = a + b + 55
so
3b² = 4b + 55
3b² - 4b - 55 = 0
(3b + 11)(b - 5) = 0
b = 5 or b = -11/3
from which
a = 15 or a = -11
a = 3b
and
a*b = a + b + 55
so
3b² = 4b + 55
3b² - 4b - 55 = 0
(3b + 11)(b - 5) = 0
b = 5 or b = -11/3
from which
a = 15 or a = -11
