Answer:
Mila had $48 initially
Explanation:
Let the amount of money they had be x
Mila spent $42; what is left would be x-42
Samuel spent $36: what is left would be x-36
So, what Mila had left is half of what Samuel has; that would be;
x-42 = 1/2(x-36)
2(x-42) = x -36
2x-84 = x -36
2x - x = 84 -36
x = $48