Which of the following multipliers will cause a number to be increased by 29.7%?
Aptitude
Percentage
Difficulty: Easy
Choose an option
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A1.297
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B12.97
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C129.7
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D1297
Answer
Correct Answer: 1.297
Explanation
### Concept & Logic
To increase a number by a certain percentage, you add that percentage of the number to the original number itself ($100\%$). The final multiplier is simply the decimal equivalent of the final percentage.
$$ \text{Final Multiplier} = 1 + \frac{\text{Percentage Increase}}{100} $$
### Step-by-Step Solution
* Let the original number be $x$. The original number represents $100\%$ of itself, or $1 \cdot x$.
* We want to increase this number by $29.7\%$.
* The increase amount is $29.7\%$ of $x$, which can be written as $0.297x$.
* The new number is the sum of the original number and the increase:
$$ \text{New Number} = x + 0.297x $$
* Factor out $x$:
$$ \text{New Number} = x(1 + 0.297) = 1.297x $$
* Therefore, the required multiplier is $1.297$.
### Exam Strategy & Shortcut
A $29.7\%$ increase means the final value is $129.7\%$ of the original.
To convert any percentage to a decimal multiplier, just divide by $100$ (move the decimal point two places to the left).
$129.7 / 100 = 1.297$.
### Common Pitfall
A very common mistake is confusing the percentage value with the decimal multiplier (e.g., choosing 129.7 or 12.97) by failing to divide by $100$ or moving the decimal point the wrong number of spaces.
### Final Answer
**Therefore, the correct answer is 1.297.**