Five plus 10 plus five equals what?
We have to add together three numbers: five, 10, and another five. One thing to remember when we’re adding three numbers is that we can add the numbers in any order. First, we could add together the two fives. Five plus five is 10. And now, we need to add the 10. 10 plus 10 equals 20.
Another way we could add the numbers is to start with number 10. Then, we could add five to make 15. 10 and five is 15. Then, we could add the second five to 15, which gives us the same total, 20.
The first way we worked out the answer was by spotting that five and five are a pair of numbers that make 10. So we added the two fives and then we added the 10. Another way to work out the answer would be to add one of the fives to number 10 to give us 15 and then add the other five to give us the same answer of 20.
Five plus 10 plus five equals 20.