Add the nearest multiple of 10 and adjust
Once the technique for adding 9 to a number has been mastered, there is no problem with adding 19, 29 or 39!
5 pages
Free
Add the nearest multiple of 10 and adjust
Once the technique for adding 9 to a number has been mastered, there is no problem with adding 19, 29 or 39!
Free Resource: Available completely free for all accounts even trial and expired ones.