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we have three plus blank is equal to ten so pause the video and try to figure out what the blank is what do I have to add to 3 to get to ten so you've had a go at it now let's see if we can do this together so over here I have three of these these I guess you could say purple these purple pinkish circles and I have 10 boxes 1 2 3 4 5 6 7 8 9 10 so one way to think about it is how many more circles do I need to add to fill up all of the boxes well let's just count that together I need to add 1 2 3 4 5 6 7 to fill up all 10 boxes so 3 plus what is equal to 10 well 3 plus 1 2 3 4 5 6 7 is equal to 10 let's do one more of these so now I have 6 plus blank is equal to 10 so again try to pause the video and see if you can figure out what the blank is what do I need to add to 6 to get to 10 let's do it together so we now have 1 2 3 4 5 6 circles we have 10 boxes here 1 2 3 4 5 6 7 8 9 10 so we just have to think about how many more circles do we need to fill up all the boxes to get to 10 because we already have 6 filled in well we need 1 2 3 4 to get to 10 so let's just fill that in 6 plus 4 is equal to 10 or we could say even that 4 plus 6 is equal to 10 either way