Question

In a school the periodical examinations are held every month. In a session during April 'X' to March 'X + 1', Rakesh, a student of class IV, section B, appeared for each of the periodical exams. The maximum total marks in each periodical exam is 50. The aggregate marks obtained by him in each periodical exam are given below.

	Year X									Year X+1
Months	April	May	June	July	Aug.	Sept.	Oct.	Nov.	Dec.	Jan.	Feb.	March
Marks	35	37	38	38	41	43	45	45	46	47	48	49

The total marks obtained in December X is what per cent more than the total marks obtained in June X?

• A. 12.8%
• B. 20.05%
• C. 24.05%
• D. 21.05%

Hint:

Take December marks minus June marks, divide by June marks, then multiply by 100.

Answer 1

The Correct Option is D

An alternative way to reach the same figure is to first reduce the fraction to its simplest form before converting to a percentage, which avoids a messy long division.

1. Difference in marks: December X - June X = $46 - 38 = 8$.
2. Form the fraction over the base: the increase is $\frac{8}{38}$, which simplifies by dividing numerator and denominator by 2 to $\frac{4}{19}$.
3. Convert using a known benchmark: $\frac{1}{19} \approx 0.0526$, so $\frac{4}{19} \approx 4 \times 0.0526 = 0.2105$.
4. Express as a percentage: $0.2105 \times 100 = 21.05\%$.

This confirms the increase from June X to December X is 21.05%. \[ \boxed{21.05\%} \]