To find how many hours Sonia work on her science project,we can multiply the working hours of Tony by the times Sonia did:
[tex]4 \frac{2}{3} \times 1 \frac{1}{4} \\ = \frac{14}{3} \times \frac{5}{4} \\ = \frac{70}{12} \\ = 5 \frac{10}{12} \\ = 5 \frac{5}{6} [/tex]
Therefore Sonia work on her science project for 5 5/6 hours.
Hope it helps!