Select the correct answer.

Which expression is equivalent to the given expression?

[tex]\[
\frac{\left(3 m^2 n\right)^3}{m n^4}
\][/tex]

A. [tex]\(\frac{9 m^5}{n}\)[/tex]

B. [tex]\(27 m^4 n\)[/tex]

C. [tex]\(\frac{27 m^5}{n}\)[/tex]

D. [tex]\(9 m^4 n\)[/tex]



Answer :

To simplify the given expression [tex]\(\frac{(3m^2n)^3}{mn^4}\)[/tex], follow these steps:

1. Expand the numerator [tex]\((3m^2n)^3\)[/tex]:

[tex]\[ (3m^2n)^3 = 3^3 \cdot (m^2)^3 \cdot n^3 \][/tex]

Compute the powers and the multiplication:

[tex]\[ 3^3 = 27,\ (m^2)^3 = m^{2 \cdot 3} = m^6,\ n^3 \][/tex]

Therefore,

[tex]\[ (3m^2n)^3 = 27m^6n^3 \][/tex]

2. Write the initial expression with the expanded numerator:

[tex]\[ \frac{27m^6n^3}{mn^4} \][/tex]

3. Simplify the denominator [tex]\(mn^4\)[/tex]:

The denominator already is in its simplest form, [tex]\(mn^4\)[/tex].

4. Combine the numerator and the denominator:

[tex]\[ \frac{27m^6n^3}{mn^4} \][/tex]

5. Simplify the expression by canceling out common factors in the numerator and the denominator:

- For [tex]\(m\)[/tex] terms: Subtract the exponent in the denominator from the exponent in the numerator:

[tex]\[ m^6 / m = m^{6 - 1} = m^5 \][/tex]

- For [tex]\(n\)[/tex] terms: Subtract the exponent in the denominator from the exponent in the numerator:

[tex]\[ n^3 / n^4 = n^{3 - 4} = n^{-1} = \frac{1}{n} \][/tex]

Combining these results:

[tex]\[ \frac{27m^6n^3}{mn^4} = 27 \cdot m^5 \cdot \frac{1}{n} = \frac{27m^5}{n} \][/tex]

So, the given expression [tex]\(\frac{(3m^2n)^3}{mn^4}\)[/tex] simplifies to [tex]\(\frac{27m^5}{n}\)[/tex].

Hence, the correct answer is:

C. [tex]\(\frac{27m^5}{n}\)[/tex]