## Algebra 1: Common Core (15th Edition)

The friend is wrong because the sum of the exponents is wrong and the product of 4 and 3 is 12, not 7. The correct answer is 12$a^{\frac{7}{10}}$
4$a^{\frac{1}{2}}$ $\times$ 3$a^{\frac{1}{5}}$ = (4$\times$3)($a^{\frac{1}{2}+\frac{1}{5}})$ = 12$a^{\frac{1(5)+1(2)}{10}}$ =12$a^{\frac{7}{10}}$