I am doing certain data-interpretation questions. In data-interpretation I am consistently encountering the percentage calculation. sometimes calculations are simple but most of the time they are time consuming mentally like inscribed below
$$ \frac{{\rm 84}}{{\rm 112}}\times 100\% =75\%$$ $$ \frac{{\rm 84}}{{\rm 107}}\times 100\% =78.5\%$$ $$ \frac{{\rm 63}}{{\rm 80}}\times 100\% =78.75\%$$ $$ \frac{{\rm 104}}{{\rm 131}}\times 100\% =79.39\%$$
In the above calculations , the percentage calculations takes too much time to calculate & come up with results mentally .
consider above two calculations or fractions which are
$$ \frac{{\rm 84}}{{\rm 112}}\times 100\% $$ $$ \&\& $$
$$ \frac{{\rm 84}}{{\rm 107}}\times 100\% $$
in this case we can immediately will says the $$ \frac{{\rm 84}}{{\rm 107}}\times 100\% $$ is maximum because of the denominator comparison.
but how to predict in the following cases or rest of the cases $$ \frac{{\rm 84}}{{\rm 107}}\times 100\% $$ $$ \frac{{\rm 63}}{{\rm 80}}\times 100\% $$ $$ \frac{{\rm 104}}{{\rm 131}}\times 100\% $$
how to say which is maximum or minimum.mentally without calculator?
Any suggestion will be welcome.