27. A number is mistakenly divided by 4 instead of multiplying by 4. What is the percentage change in the result due to this mistake?

1. A. 25%
2. B. 50%
3. C. 72.75%
4. D. 93.75%

Answer: D

Explanation

Let the number be ‘N’. The correct operation should have been multiplying by 4, so the correct result is 4N. The mistaken operation was dividing by 4, so the mistaken result is N/4. To find the percentage change, we use the formula: Percentage Change = ((Mistaken Result – Correct Result) / Correct Result) × 100. Substituting the values: Percentage Change = ((N/4 – 4N) / 4N) × 100. This simplifies to ((N – 16N)/4) / 4N × 100 = (-15N/4) / 4N × 100 = (-15N / 16N) × 100 = (-15/16) × 100 = -0.9375 × 100 = -93.75%. The negative sign indicates a decrease. The magnitude of the percentage change is 93.75%. This question tests basic percentage calculation and understanding of ‘percentage change’.