To find out if Marika's answer is correct, we need to multiply the fractions \( \frac{3}{7} \) and \( \frac{5}{7} \).
When multiplying fractions, you multiply the numerators together and the denominators together:
\[ \frac{3}{7} \times \frac{5}{7} = \frac{3 \times 5}{7 \times 7} = \frac{15}{49} \]
Marika's answer was \( \frac{15}{7} \), which is incorrect. The correct answer is \( \frac{15}{49} \).