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1. Find the ratio of the following:
(a) 75 paise to `5 (b) 72 cm to 12 m (c) 10 months to 1 year
(d) 6 hours to 3 days (e) 180 seconds to 5 minutes (f) 12 l to 214 mL

2. The ratio of monthly income to the savings of a shopkeeper is 8 : 5. If the savings is `12000,
find the income and expenditure of the shopkeeper.

3. Find the ratio of the shaded portion to the unshaded portion in the following figures:
(a) (b) (c)

Percentage

Nakul: Cheeku! Percentage is a way of comparing quantities.

Suppose you scored 15 marks out of 20 and your friend, Minki scored 18
marks out of 25.

Can you say who scored more: You or Minki?
Cheeku: Brother! I am not able to tell who scored more marks.
Nakul: Here, we can use percentage to compare, whose performance is
better?
Percentages are numerators of fractions with denominator 100 and have
been used in comparing results.
Per cent is derived from the Latin word ‘per centum’ meaning ‘per hundred’.

That is, 1 per cent means 1 out of a hundred or one hundredth.
Percent is denoted by the symbol %. Thus,
1
1% = (one hundredth)
100 1
By a certain percentage, we mean that many hundredths. 1% = 100
9
For example: 9% = 9 hundredths =
100
Percentages When Total is not Hundred

Nakul: Let’s check Cheeku! Who scored more marks?
15 18
We can write the marks scored by you and your friend Minki in the fractional form as and
respectively. 20 25

As we know, a percentage is the numerator of the fraction with a denominator 100.

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