1/4 of Mai’s height is equal to 2/5 of Jon’s height. Find the ratio of Mai’s height to Jon’s height.
Let Mai's height = m
Let Jon's height = j
We want to find \(\frac{m}{j}\)
\(\frac14\) of Mai's height   is equal to   \(\frac25\) of Jon's height  
\(\frac14\) of Mai's height  =  \(\frac25\) of Jon's height 

\(\frac14\cdot m\)  =  \(\frac25\cdot j\) 
\(\frac14\cdot m\ =\ \frac25\cdot j\)
Multiply both sides of the equation by 4
\(m\ =\ \frac85\cdot j\)
Divide both sides of the equation by j
\(\frac{m}{j}\ =\ \frac85\)
The ratio of m to j is \(\frac85\)
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