The expenses of $A$ and $B$ are in the ratio $2 : 3$. A sum of ₹ 2800 is equally divided between them. If $A$ saves ₹ 600, then $B$ saves
Aptitude
Ratio and Proportion
Difficulty: Easy
Choose an option
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A₹ 200
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B₹ 300
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C₹ 400
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D₹ 500
Answer
Correct Answer: ₹ 200
Explanation
### Concept & Income-Expense Identity
The fundamental financial identity is: $\text{Income} - \text{Savings} = \text{Expenses}$. Use this relation individually for $A$ and $B$.
### Step-by-Step Solution
1. **Given:** Total sum = ₹ 2800 divided equally. So, Income of $A = 1400$ and Income of $B = 1400$.
2. $A$ saves ₹ 600. Therefore, Expenses of $A = \text{Income} - \text{Savings} = 1400 - 600 = 800$.
3. The ratio of expenses of $A$ and $B$ is $2 : 3$. Let their expenses be $2x$ and $3x$.
4. We know $A$'s expenses are $2x = 800 \implies x = 400$.
5. Therefore, $B$'s expenses are $3x = 3(400) = 1200$.
6. $B$'s savings = Income of $B - \text{Expenses of } B = 1400 - 1200 = 200$.
### Exam Strategy & Shortcut
Realize that $A$'s expense (800) represents "2 parts" of the ratio. Thus, "1 part" is 400. $B$'s expense is "3 parts", meaning 1200. Since $B$ received 1400, savings are simply $1400 - 1200 = 200$. No complex algebra required.
### Common Pitfall
Dividing the initial ₹ 2800 sum in the $2:3$ ratio, rather than interpreting it as equal incomes.
### Final Answer
Therefore, the correct answer is **₹ 200**.