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555-605 (Medium)|   Algebra|      
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Bunuel
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Consider the formula H = 2a^3/b. If a is doubled and b is increased 03 Dec 2015, 06:30
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76% (01:09) correct 24% (01:44) wrong based on 219 sessions

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Consider the formula \(H = \frac{2a^3}{b}\). If a is doubled and b is increased by a factor of 4, by what factor is H increased?

A. 2
B. 4
C. 6
D. 8
E. 16
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A
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Consider the formula H = 2a^3/b. If a is doubled and b is increased 03 Dec 2015, 06:43
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after applying ----------- stated in question

H' = 2*(2a)^3/4b
H' = 2*8a^3/4b
H' = 8/4(H)
H' = 2 H
Thus A
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Consider the formula H = 2a^3/b. If a is doubled and b is increased 03 Dec 2015, 07:29
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H = (2a^3)/b
if a is doubled and b is incresead by factor of 4 then equation becomes
H = [2*(2a)^3] / 4b
H = 16a^3 / 4b
H = 4a^3 / b

Initially H = (2a^3) / b, Now H = (4a^3) / b which means H has been increased by a factor of 2.

Answer = A = 2
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Consider the formula H = 2a^3/b. If a is doubled and b is increased 03 Dec 2015, 08:01
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A..

h= 2 (8) A^3/(4) B

HENCE A
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Consider the formula H = 2a^3/b. If a is doubled and b is increased 06 Sep 2018, 18:18
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The question formation is wrong, when we are saying that "b" is increased by a factor of 4 ,this means that my new b will be b+4k form. If the question formed was b is increased to a factor of 4 then b will be 4k. If the answer to the question has to be A.2 then b must be written simply become 4 times.
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Consider the formula H = 2a^3/b. If a is doubled and b is increased 07 Sep 2018, 06:31
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I agree I also interpreted the question as b+4b...I would like to know what is wrong with my thinking...thanks.

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Consider the formula H = 2a^3/b. If a is doubled and b is increased 09 Sep 2018, 03:19
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H=\(\frac{2a^3}{b}\) --> H= \(\frac{a^3}{b}\)*2

The increase results in the following equation:

\(\frac{2*(2a)^3}{4b}\) --> \(\frac{16a^3}{4b}\) --> \(\frac{4a^3}{b}\) --> \(\frac{a^3}{b}\)*4
2*2=4 Hence, A.
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Consider the formula H = 2a^3/b. If a is doubled and b is increased 12 Dec 2020, 09:57
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Given: Consider the formula \(H = \frac{2a^3}{b}\).
Asked: If a is doubled and b is increased by a factor of 4, by what factor is H increased?

\(H' = \frac{2(2a)^3}{(4b)} = \frac{8}{4} * \frac{2a^3}{b} = 2 * \frac{2a^3}{b} = 2H\)

IMO A
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Consider the formula H = 2a^3/b. If a is doubled and b is increased 10 Mar 2025, 18:36
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How do you know that the question is asking H= [ 2(2a)^3 ][/ 4b ] and not [ 2(2a^3) ][/ 4b ]??
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Consider the formula H = 2a^3/b. If a is doubled and b is increased 10 Mar 2025, 23:11
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How do you know that the question is asking H= [ 2(2a)^3 ][/ 4b ] and not [ 2(2a^3) ][/ 4b ]??
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2a^3 can only mean 2(a^3). If it were (2a)^3 it would have been written that way.
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