Mental maths

 

Solve in your head using place values

a) =
b) =
c) =
d) =
e) =

 

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How to add or subtract using place values

 

To add a pair of numbers together that both end in 0, use place value to help you, by taking the place holding 0 off both numbers and placing it to one side, you then add the two numbers together and place the place holding  0 back at the end of the new number.

Example   170 + 90

                17 + 9 = 26      (0)

                = 260

                        

To add a pair of numbers together that both end in 00, use place value to help you, by taking the place holding 00 off both numbers and placing it to one side, you then add the two numbers together and place the place holding  00 back at the end of the new number.

Example   1700 + 900

                17 + 9 = 26      (00)

                = 2600

 

The same process of using place values is also used for subtraction, however your answer could be a negative number if you are subtracting a larger number from a smaller one.

Example   1700 - 900

                17 - 9 = 8      (00)

                = 800

Practice answering some more questions using your calculator.

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Year 5 Maths
Spring term

Block B
Lesson 1

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Summer term

Autumn term

 

 

 

 

 

 

 

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