Answer
$18x^{\frac{13}{20}}$
Work Step by Step
Recall the following rule: $a^{n}\cdot a^{m}=a^{n+m}$. Therefore, we obtain:
$(3x^{\frac{2}{5}})(6x^{\frac{1}{4}})$
$=(3\times6)(x^{\frac{2}{5}+\frac{1}{4}})$
$=(18)(x^{\frac{2(4)+5(1)}{20}})$
$=18x^{\frac{13}{20}}$
