Decimals
A dot that lets numbers show parts.
Parts of a whole
Not everything is a whole number. A ribbon can be 1 metre and a bit long. Decimals show the bits: 1.4 m means 1 whole metre and 4 tenths.
Tenths
Cut 1 whole into 10 equal parts: each part is a tenth, 0.1. 3 tenths is 0.3 = 3/10. The decimal point separates wholes and parts.
Hundredths
Cut 1 into 100 parts: each is a hundredth, 0.01. 45 hundredths is 0.45 – 4 tenths and 5 hundredths. It is also 45/100, and 45%.
Comparing decimals
Compare the whole numbers first, then the tenths, then the hundredths. 2.38 < 2.5 because 3 tenths < 5 tenths. Order: 1.9, 2.38, 2.5, 3.05.
Decimals in the shop
৳12.50 is 12 taka and 50 poisha. Add decimals by lining up the points: 12.50 + 5.25 = 17.75. Lengths too: 1.25 m is 1 m 25 cm.
What I learnt
- I can read and write tenths and hundredths.
- I can compare and order decimals.
- I can use decimals for money and length.