Anchor Chart · Grade 5 · 5.NBT.B.7
Dividing with Decimals
Three situations, one habit: put the decimal point in the answer before you divide.
1Decimal ÷ Whole Number
2.4
37.2
point straight up ↑
7 ÷ 3 → 2, remainder 1 · 12 tenths ÷ 3 = 4 tenths
Divide left to right, the same way as with whole numbers. The point in the answer goes straight above the point in the dividend.
2Add Zeros to Keep Going
5.75
423.00
23 ÷ 4 = 5 R3 → don't stop. 30 tenths ÷ 4, then 20 hundredths ÷ 4.
A remainder does not mean you stop. Write zeros after the decimal point, which does not change the value (23 = 23.00), and keep dividing until it comes out even or you round.
3Dividing by a Decimal
9.1 ÷ 0.2 → shift both one place → 91 ÷ 2
45.5
291.0
You can't share among 0.2 of a person. Multiply both numbers by 10 until the divisor is a whole number. The quotient does not change.
4Estimate to Check
7.2 ÷ 3 ≈ 6 ÷ 3 = 2 → 2.4 ✓
9.1 ÷ 0.2 ≈ "how many 0.2s in 9?" ≈ 45 → 45.5 ✓
Dividing by a number less than 1 gives a bigger answer. Expect it.
