Ram can do a work in 40 days. Hari is 4 times more efficient than Ram. In how many days Hari can finish the work.

Answer

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

### Step 1: Understand the given information
- Ram can complete the work in 40 days.
- Hari is 4 times more efficient than Ram.

### Step 2: Determine Ram's efficiency
- If Ram can complete the work in 40 days, we can say that his efficiency is 1 unit of work per day.
- Therefore, in 40 days, Ram completes 1 unit of work.

### Step 3: Calculate total work
- Total work can be calculated as:
\[ \text{Total Work} = \text{Time} \times \text{Efficiency} \]
- For Ram:
\[ \text{Total Work} = 40 \text{ days} \times 1 \text{ unit/day} = 40 \text{ units} \]

### Step 4: Determine Hari's efficiency
- Since Hari is 4 times more efficient than Ram, his efficiency is:
\[ \text{Hari's Efficiency} = 4 \times \text{Ram's Efficiency} = 4 \times 1 = 4 \text{ units/day} \]

### Step 5: Calculate the time taken by Hari to complete the work
- To find out how many days Hari will take to finish the same work, we can use the formula:
\[ \text{Time} = \frac{\text{Total Work}}{\text{Efficiency}} \]
- For Hari:
\[ \text{Time} = \frac{40 \text{ units}}{4 \text{ units/day}} = 10 \text{ days} \]

### Final Answer
Hari can finish the work in **10 days**.

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