Decimal Numbers
Primary 4 · Mathematics
Decimal Numbers
Lesson 2 of 4
25 min
Let's begin
At the health centre, the nurse measures Umutoni's height: 1.34 m. Umutoni wants to understand every digit. How much is the 3 worth? And the 4?
The places we already know (ones, tens, hundreds …) are on the left of the decimal point. On the right come the tenths and then the hundredths. Each place is worth one tenth of the place on its left: 10 hundredths make 1 tenth, and 10 tenths make 1 one.
| Tens | Ones | . | Tenths | Hundredths |
|---|---|---|---|---|
| 1 | . | 3 | 4 | |
| 4 | . | 3 | 6 | |
| 1 | 2 | . | 0 | 5 |
In Umutoni's height, 1.34 m:
Break a decimal into the values of its digits:
Read the whole number, say "point", then read each digit after the point on its own: 4.36 is "four point three six", and 12.05 is "twelve point zero five".
You can also say it with fractions: 4.36 is 4 and 36 hundredths.
Tip
Tenths come first after the point. Think "T comes before H": after the decimal point, the first place is Tenths and the second is Hundredths.
Work each one in your exercise book first. Then tap Show answer to check.
Which digit is in the hundredths place in 5.82?
Answer: 2
What is the value of the 7 in 3.75?
Answer: 0.7 (7 tenths)
Write 2 + 0.5 + 0.08 as one decimal.
Answer: 2.58
Write 9.03 in expanded form.
Answer: 9 + 0.03
How do you read 6.41?
Answer: six point four one
What you learned today
Sources and credits
The stories, Rwandan worked examples, diagrams and practice questions were written by Ganzaa.
Quick check
What is the value of the 8 in 5.48?
