Decimals (Tenths and Hundredths) • Topic 1 of 3

Fractions as Decimals

A decimal is another way to write a fraction. A decimal point separates the whole number part from the fractional part.

Tenths place: first digit after decimal = denominator 10 (e.g. 3/10 = 0.3)
Hundredths place: second digit after decimal = denominator 100 (e.g. 25/100 = 0.25)

Think of it like Indian currency: Rs.1 = 100 paise. 10 paise = 10/100 = 0.10. 1 paisa = 1/100 = 0.01.

Converting fractions to decimals: Make the denominator 10 or 100, then write in decimal form. Adding a zero to the right of a decimal does NOT change its value: 0.3 = 0.30.

Solved Examples

Worked Example

Write 7/10 as a decimal.

SolutionDenominator is 10, so we need 1 digit after decimal point. Numerator is 7. Write as 0.7. Check: 0.7 means 7 tenths = 7/10.

Worked Example

Write 0.45 as a fraction in simplest form.

Solution0.45 has 2 decimal places (hundredths). Write as 45/100. Simplify by dividing by 5: 9/20. Check: 9 and 20 have no common factor except 1. Answer: 9/20.

Worked Example

Add 3/10 + 5/100 and write as a decimal.

SolutionConvert 3/10 = 30/100. Add: 30/100 + 5/100 = 35/100 = 0.35. Or: 0.30 + 0.05 = 0.35.

Key Points

Tenths: first place after decimal point, denominator 10
Hundredths: second place after decimal point, denominator 100
To convert fraction to decimal: make denominator 10 or 100
Adding zeros to the right of a decimal does NOT change its value: 0.3 = 0.30

Quick Check — 4 MCQs

Tap an option to check your answer0 / 4

Q1.$\tfrac{1}{10}$ as a decimal is:

Explanation: One tenth.

Q2.$\tfrac{1}{100}$ as a decimal is:

Explanation: One hundredth.

Q3.$\tfrac{3}{10}$ as a decimal is:

Explanation: $0.3$.

Q4.The first place after the decimal point is:

Explanation: Tenths.

Practice more MCQs → 📝 Assignment · 35 marks