New
New
Year 5

Solve comparison and change problems using multiplication

I can solve comparison and change problems using multiplication.

New
New
Year 5

Solve comparison and change problems using multiplication

I can solve comparison and change problems using multiplication.

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Lesson details

Key learning points

1. A change in length can be described using multiplication.
2. The stem sentence, 'The ___ is ___ times the length of the ___' can be used to compare lengths.
3. Comparison and change problems can be represented visually to support solving them.

Common misconception

Children may say, 'Tens times taller', which is imprecise.

We say, 'Ten times the original height' because this is more precise and can be used when the scale factor is fractional.

Keywords

• Comparison - When a comparison is made, we are determining how different two objects are. In this case, how many times longer, taller or deeper an object is than another.

• Change - A comparison can also be made between an object at the start of, and then after, a change. Examples of change include a change in height of a flower due to growth.

Offer children practical examples where possible. It is important that children are fluent with their times table facts to avoid overload.
Teacher tip

Licence

This content is © Oak National Academy Limited (2024), licensed on Open Government Licence version 3.0 except where otherwise stated. See Oak's terms & conditions (Collection 2).

Starter quiz

6 Questions

Q1.
15 multiplied by 5 is equal to
Correct Answer: 75, seventyfive, seventy five, seventy-five
Q2.
40 × 3 =
Correct Answer: 120, One hundred and twenty
Q3.
Which sentences describe this image?
Correct answer: The blue ribbon is double the length of the white ribbon.
The white ribbon is the same length as the blue ribbon.
The white ribbon is two times the length of the blue ribbon.
Correct answer: The blue ribbon is two times the length of the white ribbon.
Q4.
The white ribbon is 18 cm long. How long is the blue ribbon? The blue ribbon is cm long
Correct Answer: 36 cm, 36cm, 36, thirty six centimetres
Q5.
The red ribbon is 11 cm long. Which calculation would you need to do to calculate the length of the white ribbon?
11 × 4 =
Correct answer: 11 × 3 =
11 + 3 =
Q6.
True or false: If the white ribbon is is less than 50 cm long, the blue ribbon will be less than 1 m long.
False

Exit quiz

6 Questions

Q1.
A 25 cm piece of elastic is stretched to twice its length. Which image represents the problem?
Correct Answer: An image in a quiz
Q2.
How long is the elastic now that it has been stretched to twice its original length of 25 cm? The elastic is now cm long.
Q3.
A dog is three times the height of a cat. Which bar model represents this?
Correct Answer: An image in a quiz
Q4.
The cat is 30 cm tall. The dog is three times as tall. The dog is cm tall.
Correct Answer: 90, 90 cm, ninety, Ninety
Q5.
Which expression represents the 30 cm tall cat and the dog three times the height?
Correct answer: 30 cm × 3
3 cm × 30
30 cm + 3
Q6.
Which statement describes this equation: 7 × 8 = 56
Correct answer: 56 is seven times the value of eight.
8 is seven times the value of 56
7 is eight times the value of 56
Correct answer: 56 is eight times the size of seven.