# Estimating masses

## Lesson details

### Key learning points

1. In this lesson, we will use prior knowledge to estimate masses and then work out any differences compared to the actual mass.

### Licence

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## Video

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## Worksheet

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## Starter quiz

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### 5 Questions

Q1.
What is 5kg in grams?
5000kg
500g
500kg
Others
Q2.
What is the correct language to describe the mass of this parcel?
The mass of this parcel is greater than 2kg because the parcel is higher
The mass of this parcel is greater than 2kg because the parcel is lower
Correct answer: The mass of this parcel is less than 2kg because the parcel is higher
The mass of this parcel is less than 2kg because the parcel is lower
Q3.
How much does this parcel weigh?
4g and 200g
4g and 200kg
4kg and 200kg
Q4.
What is the mass of Pepper the purple cat?
1g and 700kg
1kg and 600g
1kg and 600kg
Q5.
What is the mass of the sad pug?
2g and 200kg
2g and 300g
2kg and 200g

## Exit quiz

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### 4 Questions

Q1.
5000g or 5kg. Which mass is heavier?
5000g
5kg
Correct answer: They are the same mass
Q2.
What statement describes this picture best?
Correct answer: The can feels heavier than the mass so the can must weigh more than 500g
The can feels lighter than the mass so the can must weigh less than 500g
Q3.
Use the image below to choose the best estimate for the mass of the parcel.
125g
150g
1kg
Q4.
Find the difference
420g - 345g = 100g
420g - 345g = 70g
Correct answer: 420g - 345g = 75g
420g - 345g = 80g