Comparing Decimals: Practice at Home, Grade 4

Comparing decimals trips up many children because longer numbers look bigger. In Grade 4 they learn to compare tenths and hundredths and explain why.

What your child is working on

Which is bigger, 0.4 or 0.35? Write 0.4 as 0.40 and compare 40 hundredths with 35 hundredths: 0.4 is bigger. A number line from 0 to 1 cut into tenths shows the same thing.

Try it at home

Use money. A dime is 0.10 of a dollar and a penny is 0.01. Ask: “Which is more, 4 dimes or 35 pennies?” Count them out: 4 dimes is 40 cents and 35 pennies is 35 cents.

Then try the same idea with a ruler: 0.4 m is 40 cm and 0.35 m is 35 cm.

Where children slip

The word “longer” gets used as “bigger”. Say it together: the number of digits does not decide, the place values do. Compare tenths first, then hundredths.

Practice online

The free Compare decimals: tenths to 10 page practices comparing tenths, a good first step before the hundredths in the examples above. Later pages on the Grade 4 skills list add hundredths.