Multiply a 2-digit number by a 1-digit number using expanded multiplication (regrouping 1s to 10s) | Maths

Starter quiz

21 ones are equivalent to __________.

2 tens and one one ✓

2 tens and 1 ten

1 ten and 2 ones

2 ten and 2 ones
Look at this equation. The numbers highlighted in purple are known as ______.

products

partial products

factors ✓

addends
Select the correct representation for this multiplication.

Picture 2

Picture 3

Picture 4 ✓
The multiplication is: 73 × 2 Which short multiplication shows this correctly?

Picture 1 ✓

Picture 2
Which representation will require regrouping?

A

B ✓

C
Match the representations A, B and C to the correct multiplication equation.

A

⇔

13 × 3 ✓

B

⇔

3 × 14 ✓

C

⇔

3 × 11 ✓

Look at the image. The arrows are pointing to __________.

factors

products

partial products ✓

addends
Select the correct expanded method shown by this representation.

picture 1

picture 2 ✓
Sofia believes that you always have a 1-digit partial product when multiplying a 2-digit by a 1-digit number. What do you think?

This is always true.

This is sometimes true. ✓

This is never true.
Which multiplication will need regrouping in the ones column only?

71 × 3

10 × 3

17 × 3 ✓

77 × 3
Using Lucas’s grid model, fill in the gap for the expanded multiplication.

'32' ✓
Use expanded multiplication to calculate: 3 × 19

'57' ✓

Loading worksheet ...

Loading presentation ...

If the product of the ones digits is greater than 10, you regroup ten ones into one ten.
If the product of the ones digits is greater than ten, the partial product will be a 2-digit number.
There are similarities between the representations of multiplication.

Pupils may not align or regroup correctly leading to an inaccurate calculation.

Continue to ask what each digit that has been recorded represents. Demonstrate the regrouping using base ten blocks to help.

Regrouping - The process of unitising and exchanging between place values is known as regrouping.
Expanded multiplication - Expanded multiplication is a way of recording a calculation focusing on partitioning one or more factors and showing partial products.