Divide ₹ 671 among $A, B$ and $C$ such that if their shares be increased by ₹ 3, ₹ 7 and ₹ 9 respectively the remainder shall be in the ratio $1 : 2 : 3$.
Aptitude
Ratio and Proportion
Difficulty: Medium
Choose an option
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A₹ 110, ₹ 220, ₹ 336
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B₹ 112, ₹ 223, ₹ 336
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C₹ 105, ₹ 223, ₹ 330
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DNone of these
Answer
Correct Answer: ₹ 112, ₹ 223, ₹ 336
Explanation
### Concept & Adjusted Total
When modifications (increases or decreases) are applied to individual shares to reach a specific ratio, apply those same modifications to the total sum first to find the new distribution base.
### Step-by-Step Solution
Given:
Total initial amount = ₹ 671
Increases: $A$ by ₹ 3, $B$ by ₹ 7, $C$ by ₹ 9
New ratio of shares = $1 : 2 : 3$
1. Calculate the new total sum after the virtual increases are added:
New Total = Original Total + Sum of increases
New Total = $671 + (3 + 7 + 9) = 671 + 19 = 690$
2. Distribute this new total (₹ 690) according to the new ratio ($1 : 2 : 3$).
Total ratio parts = $1 + 2 + 3 = 6$
Value of 1 part = $\frac{690}{6} = 115$
3. Calculate the increased shares for each:
Increased share of $A = 1 \text{ part} = 115$
Increased share of $B = 2 \text{ parts} = 230$
Increased share of $C = 3 \text{ parts} = 345$
4. Find the original shares by subtracting the respective increases:
Original share of $A = 115 - 3 = 112$
Original share of $B = 230 - 7 = 223$
Original share of $C = 345 - 9 = 336$
### Exam Strategy & Shortcut
You can test the options directly. Take option (b): $112, 223, 336$. Add the increases: $112+3=115$, $223+7=230$, $336+9=345$. Check the ratio: $115 : 230 : 345$. This clearly simplifies to $1 : 2 : 3$. Also, verify the sum $112+223+336 = 671$. Both conditions met.
### Common Pitfall
Distributing the original total (₹ 671) in the ratio of $1:2:3$ and then subtracting the amounts, failing to realize the ratio applies only *after* the total pool has been increased.
### Final Answer
Therefore, the correct answer is **₹ 112, ₹ 223, ₹ 336**.