Adding and subtracting 10
When we add or subtract 10 from a number only the number in the tens column changes.
Example 1
Here is a pile of 10 books.
How many books would there be if we added 10 more books?
There would be 20 books.
10 + 10 = 20
Example 2
There are 70 pencils in the classroom.
How many pencils are left if 10 pencils are being used?
There are 60 pencils left.
70 - 10 = 60
Example 3
On Monday 4 children came to school on scooters. On Tuesday 10 more children came to school on scooters.
How many children rode a scooter to school on Tuesday?
4 + 10 = 14
10 more than 4 is 14.
14 children rode a scooter to school on Tuesday.
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More on Adding and subtracting
Find out more by working through a topic
- count4 of 23
- count5 of 23
- count6 of 23
- count7 of 23
