Subtraction and addition in the same picture — there is a CONNECTION between the two
A lesson for 1st grade math... learn the CONNECTION between addition and subtraction in an easy way! Just look at the PICTURE. We have a picture with, say, 4 raspberries and 3 blueberries. From that, we can write an addition of course — but we can ALSO write a subtraction! We just make the one part (4) or the other (3) "go away".
In the latter part of this lesson, we also look at "alligator mouth" problems — or, like Mathy likes to call them, "mammoth mouth" problems. We compare simple expressions, such as 2 + 2 and 5 − 1, and figure which one is greater than the other.
Then we solve some simple subtractions. Lastly, I give a challenging word problem concerning Ted's cars, and we solve it by DRAWING.
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See also
Fact families — video lesson for 1st grade math
Math Mammoth Subtraction 1 — topical workbook for 1st grade