Answer :

We can use proportion to solve it
[tex]135 berries -------------15min[/tex]
[tex]486 berrier --------------x[/tex]
Our x is equal to =[tex]x= \frac{486*15}{135} =54[/tex]min
Its our result
[tex]\begin{array}{ccc}135\ berries&-&15\ min\\\\486\ berries&-&\ x\ min\end{array}\ cross\ multiply\\\\\\135x=15\times485\\\\135x=7275\ \ \ \ \ |divide\ both\ sides\ by\ 135\\\\x=\frac{7275}{135}\\\\x=\frac{485}{9}\\\\x=53\frac{8}{9}\ (min)\approx54\ (min)[/tex]