Rename?!?
Interesting terminology.
To do the problem the mixed number needs to be changed into an improper fraction ( is this renaming? ). (4 1/4)
(4*4+1)/4
= 17/4
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17/4 - 3/4
= 14/4 = 7/2 = 3 1/2 as mixed number
Explain why it is necessary to rename 4 1/4 if you subtract 3/4 from it?