Manhattan flash cards

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by GMATGuruNY » Sat Mar 19, 2011 4:18 am
gmatapril wrote:Consider the formula
H = 2a^3/b

If a is doubled and b is increased be a factor of 4, by what factor is H increased.
We can plug in values.

Let a=1, b=1.
H = (2* 1^3)/1 = 2.

New a = 2*1 = 2, new b = 4*1 = 4.
New H = (2* 2^3)/4 = 4.

New H/Old H = 4/2 = 2.
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by gmatapril » Sat Mar 19, 2011 4:26 am
thank you. can you please clear this what does this mean that b is increased by a factor of 4, are we multiplying with 4 or adding by 4.
GMATGuruNY wrote:
gmatapril wrote:Consider the formula
H = 2a^3/b

If a is doubled and b is increased be a factor of 4, by what factor is H increased.
We can plug in values.

Let a=1, b=1.
H = (2* 1^3)/1 = 2.

New a = 2*1 = 2, new b = 4*1 = 4.
New H = (2* 2^3)/4 = 4.

New H/Old H = 4/2 = 2.

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by GMATGuruNY » Sat Mar 19, 2011 4:36 am
gmatapril wrote:thank you. can you please clear this what does this mean that b is increased by a factor of 4, are we multiplying with 4 or adding by 4.
GMATGuruNY wrote:
gmatapril wrote:Consider the formula
H = 2a^3/b

If a is doubled and b is increased be a factor of 4, by what factor is H increased.
We can plug in values.

Let a=1, b=1.
H = (2* 1^3)/1 = 2.

New a = 2*1 = 2, new b = 4*1 = 4.
New H = (2* 2^3)/4 = 4.

New H/Old H = 4/2 = 2.
To increase by a factor of x means to multiply by x.
Thus, if b is increased by a factor of 4, then b is multiplied by 4.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
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].
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