Given $\frac { 50 } { 10 }$ And $\frac { 53 } { 13 }$

Essay

Given $\frac { 50 } { 10 }$ and $\frac { 53 } { 13 }$ , why are we able to "cancel" the zeros in $\frac { 50 } { 10 }$ but not able to "cancel" the 3s in $\frac { 53 } { 13 }$
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