Carpentar (Rahul) income `Rs. 600` per day if salary is increase `20%` and work is decrease `12.5%` then what will effect on his income ?

Options

A. a) `5%` increase
B. b) `8%` decrease
C. c) `7%` decrease
D. d) `10%` increase

Answer

To find the effect on Rahul's income after a 20% increase in salary and a 12.5% decrease in work, we can follow these steps:

### Step 1: Identify the percentage increase and decrease
- **Increase in salary**: 20%
- **Decrease in work**: 12.5%

### Step 2: Use the formula for net effect of percentage change
The formula to find the net effect of two percentage changes is:
\[ \text{Net Effect} = A + B + \frac{AB}{100} \]
Where:
- \( A \) is the percentage increase (20%).
- \( B \) is the percentage decrease (-12.5%).

### Step 3: Substitute the values into the formula
Substituting the values into the formula:
\[ \text{Net Effect} = 20 + (-12.5) + \frac{20 \times (-12.5)}{100} \]

### Step 4: Calculate the components
1. Calculate \( 20 + (-12.5) \):
\[ 20 - 12.5 = 7.5 \]

2. Calculate \( \frac{20 \times (-12.5)}{100} \):
\[ \frac{-250}{100} = -2.5 \]

### Step 5: Combine the results
Now combine the results:
\[ \text{Net Effect} = 7.5 - 2.5 = 5 \]

### Step 6: Interpret the result
The net effect is 5%, which indicates that Rahul's income will increase by 5%.

### Conclusion
Therefore, Rahul's income will increase by **5%** after the changes in salary and work.

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