If 10 men can do a work in 20 days, then how many men can do the same work in 4 days?
(a)60 men
(b)20 men
(c)50 men
(d)40 men

Options

A. 60 men
B. 20 men
C. 50 men
D. 40 men

Answer

To solve the problem, we can use the concept of work done, which relates the number of men, the number of days, and the amount of work.

### Step-by-Step Solution:

1. **Understand the Given Information**:
- 10 men can complete the work in 20 days.

2. **Calculate Total Work in Man-Days**:
- Total work can be calculated as:
\[ \text{Total Work} = \text{Number of Men} \times \text{Number of Days} \]
- Here, Total Work = 10 men × 20 days = 200 man-days.

3. **Set Up the Equation for the New Scenario**:
- We want to find out how many men (let's call this \( M_1 \)) are needed to complete the same work in 4 days.
- The equation will be:
\[ M_1 \times 4 \text{ days} = 200 \text{ man-days} \]

4. **Solve for \( M_1 \)**:
- Rearranging the equation gives:
\[ M_1 = \frac{200 \text{ man-days}}{4 \text{ days}} = 50 \text{ men} \]

5. **Conclusion**:
- Therefore, 50 men can complete the same work in 4 days.

### Answer:
(c) 50 men