EN
BuilderGrades 4–5⏱ 15 min

Decimals

Shade a hundred grid to build tenths and hundredths, read them as fractions and words, and compare tricky pairs like 0.5 and 0.45.

Standards: 4.NF.C.64.NF.C.75.NBT.A.3

1Wonder

A runner finishes in 9.58 seconds. A bottle holds 0.5 litres. A price tag says $2.75. What do the numbers after the point mean?

2Explore

Decimal grid

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Turn your phone sideways, or open this lesson on a tablet or computer. The explanation and quiz below work here.

Drag across the grid to shade it0.37= 37/10037 hundredthsOnes0Tenths3Hundredths7.01SillyChili
What to do
Ones
0
Tenths
3
Hundredths
7
Try this
  • Drag across the grid to shade 3 columns. What decimal is that? What fraction?
  • Now shade 37 small squares. How do you write it? How do you say it?
  • Add 1 to the ones. Where does the point move on the number line?
  • Choose Compare two and press Next pair. Which is bigger: 0.5 or 0.45? Is 0.3 the same as 0.30?

3Explain

0.3= 3/10SillyChili
Step 1 of 5

Tenths

Cut one whole into 10 equal parts. Each part is one tenth: 1/10 = 0.1. Three parts are 3/10 = 0.3.

Reading a decimal

Each place after the point is ten times smaller than the one before: tenths, then hundredths. To compare decimals, compare place by place from the left.

4Practice

Question 1 of 5

What decimal does this grid show?

5Recap

  • Tenths: one whole cut into 10 parts. 0.1 = 1/10.
  • Hundredths: one whole cut into 100 parts. 0.01 = 1/100.
  • In 2.47: 2 ones, 4 tenths, 7 hundredths.
  • Compare decimals place by place: 0.5 > 0.45.
  • 0.3 = 0.30: zeros at the end don’t change the value.