Question 774892
Essentially cut the 15 gallons into 6 equal parts (meaning division by 6) and then count 5 of those parts.


This way:

{{{(5/6)*15}}}


{{{(5/(2*3))(3*5)}}}


{{{(5*3*5)/(2*3)}}}


{{{(5*cross(3)*5)/(2*cross(3))}}}


{{{(5*5)/2}}}


{{{25/2}}}