bridging numbers

[workshy]

is it just me or is this THE most complicated way of adding up???

this is how I understand it because I may have it wrong.....

25 + 17

you count up on a number line from 25 to 30, so you have used 5 of the 17. You then count up on a number line to 40, so you have used another 10. Then you continue counting up the number line until you have used all the 17 and end up at 42

what on earth is wrong with

25
17+

42

geez I'm confused!

I would go, 25, 35, 40, 42. just been looking into it and can't understand why they have to go to the next 10 first.( I only skimmed the maths book i thought children were taught to count in tens from any number, but then i may be wrong.

the way you have posted it, you would forget which bits of the 17 you have used, well I would anyway.

I would have added 10 then 7 personally but my DD2 tells me I'm wrong and she has to take it up to the next 'tens' number

my DD1 who is 2 years older says 'dur is that all you are doing? that's soooooo easy!' at which point she is politely reminded to mind her own business