explain how the models in questions in 1 and 2 are the same
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When dividing with fractions, you "keep, change, and flip" the problem.
This means that the 4 becomes 1/4, so they are equal to each other.
What it looks like:
[tex]\frac{1}{2}[/tex] ÷ 4 -> [tex]\frac{1}{2}[/tex] x [tex]\frac{1}{4}[/tex]
[tex]\frac{1}{2}[/tex] = keep
÷ = change to x
4 = flip to [tex]\frac{1}{4}[/tex]