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MathRevolution
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Which of the following is equal to 3^m * 7^(m-1)? Updated on: 17 Oct 2024, 08:45
Originally posted by MathRevolution on 07 Mar 2017, 01:06.
Last edited by Bunuel on 17 Oct 2024, 08:45, edited 2 times in total.
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C
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71% (01:15) correct 29% (01:46) wrong based on 238 sessions

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Which of the following is equal to \(3^m7^{m-1}\)?

A. \( 3(21^m)\)

B. \( 7(21^m)\)

C. \( 3(21^{m-1})\)

D. \( 7(21^{m-1})\)

E. \( 21^{m-1}\)
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C
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0akshay0
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Which of the following is equal to 3^m * 7^(m-1)? 07 Mar 2017, 01:53
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MathRevolution
Which of the following is equal to
\(3^m7^{m-1}\)?


\(A. 3(21^m)\)
\(B. 7(21^m)\)
\(C. 3(21^{m-1})\)
\(D. 7(21^{m-1})\)
\(E. 21^{m-1}\)
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\(3^m7^{m-1}\)
\(3*3^{m-1}7^{m-1}\)
\(3(21^{m-1})\)

Hence option C is correct
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Which of the following is equal to 3^m * 7^(m-1)? 07 Mar 2017, 10:15
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0akshay0
Can you explain your working out in depth. I am not understanding.

Or Bunuel can you help me.
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Which of the following is equal to 3^m * 7^(m-1)? 07 Mar 2017, 10:34
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matthewsmith_89
0akshay0
Can you explain your working out in depth. I am not understanding.

Or Bunuel can you help me.
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\(3^m*7^{m-1}\)

\((3*3^{m-1})*7^{m-1}\)

\(3*(3^{m-1}*7^{m-1})\)

\(3*(3*7)^{m-1}\)

\(3*(21^{m-1})\)

Hope it's clear.
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Which of the following is equal to 3^m * 7^(m-1)? 09 Mar 2017, 02:41
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==> From \(3^m7^m^-^1=3(3^m^-^1)(7^m^-^1)=3(3*7)^m^-^1=3(21^m^-^1)\), the answer is C.

Answer: C
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Which of the following is equal to 3^m * 7^(m-1)? 09 Mar 2017, 03:49
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3^m x 7^(m-1) = 3 x 3^(m-1) x 7^(m-1) = 3 x (3 x 7)^(m-1) = 3 x 21^(m-1) Option C
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Which of the following is equal to 3^m * 7^(m-1)? 17 Oct 2024, 05:56
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Hey,

Why are we multiplying the equation with a 3? Are we factoring it out?

Bunuel
matthewsmith_89
0akshay0
Can you explain your working out in depth. I am not understanding.

Or Bunuel can you help me.

\(3^m*7^{m-1}\)

\((3*3^{m-1})*7^{m-1}\)

\(3*(3^{m-1}*7^{m-1})\)

\(3*(3*7)^{m-1}\)

\(3*(21^{m-1})\)

Hope it's clear.
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Which of the following is equal to 3^m * 7^(m-1)? 17 Oct 2024, 08:49
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mikhailhx1
Hey,

Why are we multiplying the equation with a 3? Are we factoring it out?

Bunuel
matthewsmith_89

Which of the following is equal to \(3^m7^{m-1}\)?

A. \( 3(21^m)\)
B. \( 7(21^m)\)
C. \( 3(21^{m-1})\)
D. \( 7(21^{m-1})\)
E. \( 21^{m-1}\)


0akshay0
Can you explain your working out in depth. I am not understanding.

Or Bunuel can you help me.

\(3^m*7^{m-1}\)

\((3*3^{m-1})*7^{m-1}\)

\(3*(3^{m-1}*7^{m-1})\)

\(3*(3*7)^{m-1}\)

\(3*(21^{m-1})\)

Hope it's clear.
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Yes, we are breaking \(3^m\) into \(3 * 3^{(m-1)}\) so that both 3 and 7 have the same exponent (m-1). This allows us to apply the rule \(a^m * b^m = (a*b)^m\).
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