Question

Simplify $(\frac{3}{8}{)}^4\times (\frac{7}{5}{)}^4$

• A. $(\frac{21}{45}{)}^4$
• B. $(\frac{10}{13}{)}^4$
• C. $(\frac{21}{40}{)}^4$
• D. $(\frac{21}{48}{)}^4$

Answer 1

The correct option is C $(\frac{21}{40}{)}^4$

By the Laws of Exponents, we know that $a^m\times b^m=(ab{)}^m$
$\Rightarrow$ $(\frac{3}{8}{)}^4\times (\frac{7}{5}{)}^4=(\frac{3\times 7}{8\times 5}{)}^4=(\frac{21}{40}{)}^4$