Let
x-------> total peanuts originally from the bag
we know that
1) Phillip took 1/3 of the peanuts from the bag--------> (1/3)*x
remaining=x-(1/3)*x-------> (2/3)*x
2) Joy took 1/4 of the remaining peanuts-------> (1/4)*[(2/3)*x]----> (1/6)*x
remaining= (2/3)*x-(1/6)*x------> (1/2)*x
3) Brett took 1/2 of the remaining peanuts------> (1/2)*(1/2)*x-----> (1/4)*x
remaining= (1/2)*x-(1/4)*x-------> (1/4)*x
4) Preston took 10 peanuts------> 10
(1/4)*x-10=71----> multiply by 4 both sides----> x-40=284----> x=324 peanuts
5) Total originally peanuts from the bag is equal to 324 peanuts
6) Phillip took (1/3)*x-----> (1/3)*324=108 peanuts
7) Joy took (1/6)*x------> (1/6)*324=54 peanuts
8) Brett took (1/4)*x------> (1/4)*324=81 peanuts
9) Preston took 10
so
check
108+54+81+10=253
remaining=324-253------> remaining=71-------> is correct