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 Total Hours Needed for the Project
The man works 8 hours a day for 5 days. To find the total hours needed to complete the project, we multiply the number of hours he works each day by the number of days he works.

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

### Step 2: Determine the New Daily Hours Required
Now, we need to find out how many hours he must work each day to complete the same project in 4 days. We know that the total hours required to complete the project is 40 hours.

Let \( x \) be the number of hours he needs to work each day. Since he wants to complete the work in 4 days, we can set up the equation:

\[ \text{Total Hours} = \text{Hours per Day} \times \text{Number of Days} \]
\[ 40 \, \text{hours} = x \, \text{hours/day} \times 4 \, \text{days} \]

### Step 3: Solve for \( x \)
To find \( x \), we can rearrange the equation:

\[ x = \frac{40 \, \text{hours}}{4 \, \text{days}} = 10 \, \text{hours/day} \]

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

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