Percentage
- CBSE · NCERT Class 8 Part 2, Ch 1 Fractions in Disguise
A percentage is a fraction with 100 as its denominator, so 25% means 25 out of every 100, the same as 25/100 or 1/4.
Per cent means "out of a hundred". The sign % stands for it. Percentages make it easy to compare parts of different wholes, because every one is scaled to 100.
To turn a fraction into a percentage, multiply it by 100. So 3/5 × 100 = 60%. To find a percentage of an amount, turn the percentage back into a fraction first. 20% of 450 is 20/100 × 450 = 90.
A small example
A box holds 40 pens, and 14 of them are blue. What percentage are blue? The fraction is 14/40. Multiply by 100: 14/40 × 100 = 35. So 35% of the pens are blue, and the other 65% are not.
Where marks go
Question 12 of the CBSE Maths Standard sample paper for 2026-27 mixes a percentage with a mean. A group's mean age is 35. The men's mean is 38 and the women's is 30. What percentage of the group are women?
The marking scheme works out that men and women are in the ratio 5 : 3. So women are 3 out of every 8, and 3/8 × 100 = 37.5%. It is a 1-mark multiple-choice question, with no part marks. Writing the women's share as 3/5 instead of 3/8 gives 60%, which is wrong.
Sources
Facts last checked against these sources on 30 September 2026.
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