Question 1203899
The question is for the sand in the mixture.


First Pile
{{{1/4}}} sand


Second Pile
{{{3/8}}} sand



Making the mixture:  24 yd^3 first and 40 yd^3 second

{{{24(1/4)+40(3/8)}}}

{{{6+15}}}

{{{highlight(21)}}}{{{highlight(yd^3)}}}{{{sand}}}