Hello!
Answer:

Explanation:
→ We want how many hours did he work in all.
→ We know that Aldo worked 7.9 hours each day.
→ So we have this table:
days 1 6
hours 7.9 x
→ We want the value of x.
→ Let's use the method of the cross:

→ Simplify the equation:

Conclusion:
Aldo worked 47.4 hours in all.