A man working 8 hours a day takes 5 days to complete a project. How many hours a day must he work to complete. It in 4 days?

Answer

To solve the problem step by step, we can follow these instructions:

### Step 1: Calculate the total hours worked in 5 days
The man works 8 hours a day for 5 days. To find the total hours worked, we multiply the number of hours per day by the number of days.

\[ \text{Total hours} = \text{Hours per day} \times \text{Number of days} = 8 \, \text{hours/day} \times 5 \, \text{days} = 40 \, \text{hours} \]

### Step 2: Determine the daily hours needed to complete the project in 4 days
Now, we need to find out how many hours he must work each day to complete the same project in 4 days. We take the total hours calculated in Step 1 and divide it by the new number of days (4 days).

\[ \text{Hours per day} = \frac{\text{Total hours}}{\text{Number of days}} = \frac{40 \, \text{hours}}{4 \, \text{days}} = 10 \, \text{hours/day} \]

### Conclusion
The man must work **10 hours a day** to complete the project in 4 days.

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