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505-555 (Easy)|   Algebra|      
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Bunuel
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In the formula a=b^2c, if b is multiplied by 2 and c is multiplied by 12 Mar 2018, 21:59
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D
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15% (low)

Question Stats:

73% (00:46) correct 27% (00:47) wrong based on 159 sessions

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In the formula \(a=b^2c\), if b is multiplied by 2 and c is multiplied by 3, then \(a\) must be multiplied by

A. 4
B. 6
C. 9
D. 12
E. 18
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D
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In the formula a=b^2c, if b is multiplied by 2 and c is multiplied by 12 Mar 2018, 22:02
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Bunuel
In the formula \(a=b^2c\), if b is multiplied by 2 and c is multiplied by 3, then \(a\) must be multiplied by

A. 4
B. 6
C. 9
D. 12
E. 18
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7. Algebra



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Schools: IIM (A) ISB '24
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In the formula a=b^2c, if b is multiplied by 2 and c is multiplied by 13 Mar 2018, 05:02
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Bunuel
In the formula \(a=b^2c\), if b is multiplied by 2 and c is multiplied by 3, then \(a\) must be multiplied by

A. 4
B. 6
C. 9
D. 12
E. 18
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\(a=b^2c\)

if b is multiplied by 2 and c is multiplied by 3,


\(a_new=(2b)^2(3c)\)

\(a_new=12(b)^2(c)\)

i.e. a Must be multiples by 12

Answer: option D
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In the formula a=b^2c, if b is multiplied by 2 and c is multiplied by 13 Mar 2018, 07:45
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Bunuel
In the formula \(a=b^2c\), if b is multiplied by 2 and c is multiplied by 3, then \(a\) must be multiplied by

A. 4
B. 6
C. 9
D. 12
E. 18
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Plug in b = 2 and c = 3

So, \(a = b^2c\) , ie \(a = 2^2*3\)

Hence, answer must be (D) 12
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In the formula a=b^2c, if b is multiplied by 2 and c is multiplied by 13 Mar 2018, 23:54
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Bunuel
In the formula \(a=b^2c\), if b is multiplied by 2 and c is multiplied by 3, then \(a\) must be multiplied by

A. 4
B. 6
C. 9
D. 12
E. 18
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a = b^2

Multiplying b by 2 we get 2b

Multiplying c by 3 we get 3c

Now, a = (2b)^2 * 3c

a = 12b^2 * c

a needs to be multiplied by 12 (D).
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In the formula a=b^2c, if b is multiplied by 2 and c is multiplied by 14 Mar 2018, 16:01
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Bunuel
In the formula \(a=b^2c\), if b is multiplied by 2 and c is multiplied by 3, then \(a\) must be multiplied by

A. 4
B. 6
C. 9
D. 12
E. 18
Show more

If b is multiplied by 2 and c is multiplied by 3, then we will have (2b)^2 * (3c) = 12b^2 * c, which is 12 times its original value. Since the right hand of the original equation has increased by a factor of 12, we must multiply the left side of the equation by 12 as well.

Answer: D
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In the formula a=b^2c, if b is multiplied by 2 and c is multiplied by 19 Mar 2018, 11:35
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SOLUTION



We are given:
    • \(a\)= \(b^2\) c

If we multiply \(b\) by \(2\) and \(c\) by \(3\), then \(b\) becomes \(2b\) and \(c\) becomes \(3c\).
Thus, the new value of \(a\) is equal to:

    • =\((2b)^2\) *\((3c)\)
    • =\(4*\)\(b^2\)*\(3*c\)
    • = \(12\)* (\(b^2\) *\(c\))
    • =\(12*a\)
Therefore, \(a\) must be multiplied by \(12\).

Answer: D
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In the formula a=b^2c, if b is multiplied by 2 and c is multiplied by 18 Aug 2020, 07:13
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Hi, what if either b or c or both are equal to 0?

I think that the question did not indicate that these conditions are invalid. I know that 12 will be the answer, but the question is just poorly formulated, it should not be "must".
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