Use knowledge of doubles to calculate near-doubles | Maths

Starter quiz

When we add two equal addends, we are ______

doubling ✓

halving
What number would complete this bar model?

'2' ✓
Tick all the correct statements.

Half of 8 is 4 ✓

Half of 4 is 2 ✓

Double 4 is 2

Double 2 is 4 ✓
What is the missing number? Half of ______ is 3

8

7

6 ✓

5
Who is correct?

Sam

Jacob ✓
Sam is 8 years old. She is double the age of her brother. How old is her brother?

3 years old

4 years old ✓

1 years old

2 years old

Exit quiz

What near double is the representation showing?

6 + 5

5 + 5 ✓

5 + 4
What near double is the representation showing?

3 + 3 ✓

3 + 4

4 + 5
Which of these double facts would help to solve this near-double problem? 2 + 3 =

1 + 1

2 + 2 ✓

3 + 3 ✓

5 + 5
Finish the sentence. Near doubles always have ______

two odd addends.

two even addends.

one odd and one even addend. ✓
What is the missing number in this bar model?

4 ✓

3

2

5
Jacob ran 4 laps of the track. Then he ran another 3 laps. How many laps did he run in total?

'7' ✓

Worksheet

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Lesson Details

Key learning points

Knowing double facts helps you to calculate near-doubles.
If 2 + 2 is equal to 4, then 2 + 3 is equal to one more than 4 which is 5

Common misconception

Children could try to apply this idea to other near-double facts that may be more easily solved using other strategies.

0 + 1 and 1 + 2 are near-doubles, but these are more easily solved using the 'one more'/ 'one less' strategy. Explore this together before leading children to the most efficient strategy for calculating.

Keywords

Double - To become twice as many.
Near-double - A near-double is a number close to a double.
Addends - Any of the numbers that are added together.