For reasons I would rather not go in to, my 6 year old is doing schoolwork at home. I collect the work at start of week and only see receptionist so nobody actually explains the work. We have to add one ten and obese unit to some numbers that we've been given. If I'm right that means adding on 11?
Now its this bit I don't get. Think of numbers which have twice as many one's as tens and think of numbers with twice as many tens as ones. What does this mean? Examples would be appreciated!