So can we find an easy way to add numbers that end in 9.

Can we come up with a rule?

What could we do to make adding numbers ending in 8 or 7?

So can we find an easy way to add numbers that end in 9.

Can we come up with a rule?

What could we do to make adding numbers ending in 8 or 7?

© 2017 Chestnut 2 – a year 5 ORCS blog

Theme by Anders Noren — Up ↑

Translate ยป

November 22, 2017 at 11:43 am

To add numbers that end in 9

First we add 1 to make the ones column = 0

Then we do the calculation to find the answer.

But we need to take away 1 to get the correct answer.

For example

164 + 59

add 1 to 59 to make 60

then do 164 + 60 = 224

finally take away 1 from 224 to get correct answer which is 223

Ayan, Milana, Rayaan, Mohammed and Alamin