Explain how to use long multiplication to multiply two 2-digit numbers with regrouping | Maths

Starter quiz

Look at the equation 45 × 23 = 1,035 45 and 23 are both __________.

addends

quotients

factors ✓

products
Use known facts to match the expression to its product.

30 × 6

⇔

180 ✓

70 × 9

⇔

630 ✓

5 × 50

⇔

250 ✓

12 × 70

⇔

840 ✓
Look at the long multiplication below. How many tens have been regrouped? ______ ten(s) has been regrouped.

'1' ✓
Look at the long multiplication below. Calculate the missing partial product.

'636' ✓
Use long multiplication to calculate. A football match is selling tickets at £35 It sells 22 tickets on Tuesday. How much money was made altogether? £______

'770' ✓
Use long multiplication to calculate. A concert is selling tickets at £37 each. It sells 114 tickets on Thursday. How much money was made altogether? £______

'4,218' ✓

Exit quiz

Select the correct long multiplication layout for 43 × 27
Look at the equation 145 × 23 = 3,335 145 and 23 are both __________.

addends

quotients

factors ✓

products
Look at the long multiplication below. The number circled is known as a partial ______.

'product' ✓
T-shirts are displayed on racks. Each display rack holds 45 t-shirts, and there are 34 display racks in the shop. Which equation represents this?

45 × 34 = ✓

45 × 45 =

34 × 34 =
T-shirts are displayed on racks. Each display rack holds 45 t-shirts, and there are 34 display racks in the shop. How many t-shirts are there? ______ t-shirts

'1,530' ✓
There are 86 volunteers involved in each leg of the Olympic torch relay. If there are 48 legs of the relay, how many volunteers are involved in total?

'4,128' ✓

Worksheet

Loading worksheet ...

Presentation

Loading presentation ...

Video

Lesson Details

Key learning points

Calculate the partial products.
Add the partial products to recombine.
Regroup when numbers bridge 10 or 100

Common misconception

Pupils forget to include regrouped values when multiplying.

Decide on a place and structure for regrouped values - they are included at the top of the algorithm in these lessons to avoid confusion with addition regrouping when partial products are summed. Ensure this is clearly modelled.

Keywords

Partial product - Any of the multiplication results we get leading up to an overall multiplication result is a partial product.
Regroup - The process of unitising and exchanging between place values is known as regrouping.