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If 3/(10^4) = x%, then x = GMAT percents question

If 3/(10^4) = x%, then x = (A) 0.3(B) 0.03(C) 0.003(D) 0.0003(E) 0.00003 Never write the percent sign or use it in calculation. Always make x% = x/100 immediately. GMAT #GRE #Quant #MIM #MBA I need to write a few more things to make this human-friendly according to my SEO software, so let me tell … Read More

Debater: The average amount of overtime per month GMAT

Debater: The average amount of overtime per month GMAT Always consider outliers when you’re faced with an average. In this case, note that the Manufacturing Division DOES REPRESENT the company as a whole–we’re told that early in the question. Debater: The average amount of overtime per month worked by an employee in the manufacturing division … Read More

(n+1)^3 – ((n^3)+1) GMAT cubic binomial expansion

If n is a positive integer, which of the following could be equal to ((n+1)^3)−((n^3)+1)? A. 7^3(6^3−1) B. 7^3(6^3+1) C. 2∗26∗27 D. 3∗31∗32 E. 0 You can do this step-by-step by hand, but it will be a hell of a lot easier if you have the cubic expansion for a binomal handy: (a+b)^3 = a^3 … Read More

If 3x – 2y = 32 and sqrt (3x) – sqrt (2y) = 4 GMAT

This looks like something where we ought to be able to square the second equation as it stands–but that will give you a polynomial with a root in the middle. Bad. However, if you look at the left equation as a difference of squares (where the right equation is one of the two brackets), then … Read More