Lalit earns Rs. x per day and spends Rs. y per day. How much does he save in 30 days?

Answer

To find out how much Lalit saves in 30 days, we can follow these steps:

### Step 1: Calculate Lalit's total earnings in 30 days.
Lalit earns Rs. x per day. Therefore, in 30 days, his total earnings can be calculated as:
\[ \text{Total Earnings} = x \times 30 = 30x \]

### Step 2: Calculate Lalit's total spending in 30 days.
Lalit spends Rs. y per day. Therefore, in 30 days, his total spending can be calculated as:
\[ \text{Total Spending} = y \times 30 = 30y \]

### Step 3: Calculate Lalit's savings in 30 days.
To find out how much Lalit saves, we subtract his total spending from his total earnings:
\[ \text{Savings} = \text{Total Earnings} - \text{Total Spending} = 30x - 30y \]

### Step 4: Simplify the savings expression.
We can factor out 30 from the savings expression:
\[ \text{Savings} = 30(x - y) \]

Thus, Lalit's savings in 30 days is:
\[ \text{Savings} = 30(x - y) \]

### Final Answer:
Lalit saves Rs. 30(x - y) in 30 days.

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