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Introducing fraction subtraction using models.
Then... same problem done using standard mathematics, proving we ONLY do subtraction on the NUMERATORS.
0:52 example with common denominators
1:09 second example with common denominators, but THIS one can be reduced.
1:34 what about fractions with different denominators. Example: change one fraction to get a common denominator.
2:21 last example, change both fractions for common denominator.
3:26 Summary of fraction subtraction