The sum of two numbers is 22. Five times one number is equal to 6 times the other. The bigger of the two numbers is
Aptitude
Problems on Numbers
Difficulty: Easy
Choose an option
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A10
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B12
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C15
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D16
Answer
Correct Answer: 12
Explanation
## Concept & Logic
When a multiple of one quantity equals a multiple of another, their ratio is the inverse of those multipliers. This ratio can then be distributed over their total sum.
$$ a \cdot x = b \cdot y \Rightarrow \frac{x}{y} = \frac{b}{a} $$
## Step-by-Step Solution
* **Given:** Let the numbers be $x$ and $y$. Sum $x + y = 22$. Also, $5x = 6y$.
* **Calculation / Deduction:**
* From $5x = 6y$, we find the ratio of $x$ to $y$:
* $$ \frac{x}{y} = \frac{6}{5} $$
* This means the numbers are in the ratio of $6:5$. Let them be $6k$ and $5k$.
* Substitute into the sum equation:
* $6k + 5k = 22$
* $11k = 22$
* $k = 2$
* The numbers are $6(2) = 12$ and $5(2) = 10$.
* The bigger number is $12$.
## Exam Strategy & Shortcut
**Mental Math via Proportions:** $5$ times one is $6$ times the other, meaning the numbers are in a $6:5$ ratio. Total parts $= 11$. Sum is $22$, which is exactly double the total parts. Therefore, the numbers are just double the ratio figures: $12$ and $10$. The larger is instantly $12$.
## Common Pitfall
A frequent mistake is writing the ratio as $5:6$ instead of $6:5$ when translating $5x = 6y$. Always double-check inverse proportionality: the number with the smaller coefficient must be the larger value to balance the equation.
## Final Answer
**Therefore, the correct answer is 12.**