L3 · Dividing decimals

Learning goal

“I can divide decimals by 1-digit whole numbers (and divide whole numbers to get a decimal answer), place the decimal point correctly, check with multiplication - and I know when a problem is a technology problem: a divisor with more than one digit.”

Dividend — the number being divided: in 8.4 / 2, the dividend is 8.4.

Divisor — the number dividing: in 8.4 / 2, the divisor is 2.

Quotient — the answer to a division.

Technology problem — a computation the curriculum expects you to do with a calculator or computer - here, any division whose divisor has more than 1 digit. Your job there is a smart estimate and a reasonableness check.

Worked example

8.4 / 2. Step 1 (estimate): 8.4 split in half is a bit more than 4. Expect about 4.2. Step 2 (place the point FIRST): in long division, the quotient's decimal point sits directly above the dividend's. Put it there before computing - the places then take care of themselves. Step 3 (divide place by place): 8 ones / 2 = 4 ones. 4 tenths / 2 = 2 tenths. Quotient: 4.2. Step 4 (check): 4.2 x 2 = 8.4 - the multiplication check from G7U01 L4, still the referee.

Check yourself — explain it

Placing the quotient's point before dividing helps because...

Paired problem — example still visible

9.6 / 4 -> point up; 9 / 4 = 2 r1; continue: 16 tenths / 4 = 4 -> 2.4

Faded completion — last step is yours

"7.65 / 3: point above the point; 7 / 3 = 2 r1; 16 tenths / 3 = 5 r1; 15 hundredths / 3 = ___; quotient = ___" -> 5; 2.55

Ready to practise?

10 scored questions with a 3-rung hint ladder. Mastery needs 8/10 plus both gate questions.

Start practice →Take the unit quiz