How do you simplify #4.7-1.9#?
2 Answers
The explanation takes longer than doing the actual mathematics.
Explanation:
A portion of this calculation is done in my mind
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Take 1 from the 4 and put it with the 0.7
But
Because we have removed 1 from the 4 it becomes 3.
It looks like this:
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Putting it all together:
2.8
Explanation:
think of 1.9 as
So if you subtract 2 you have removed 0.1 too much. So you put it back.
Now put back the 0.1