we know that
total amount of sap =[3*(1/4)+2*(3/8)+4*(5/8)+1*(1)]
total amount of sap =[(3/4)+(6/8)+(20/8)+(1)]
total amount of sap =[(3/4)+(3/4)+(10/4)+(4/4)]
total amount of sap =[20/4]
total amount of sap =5 gallons
total of trees=10
[amount of sap collected from each tree]=total amount of sap/total of trees
[amount of sap collected from each tree]=5/10----> 0.5 gallons per tree
the answer is
0.5 gallons