15.
I had x before the movie.
x - 13.50 = 26.50
Add 13.50 to both sides of the equation:
x = 40
I had $40 before the movie.
16.
The original balance was x.
x - 161.15 = 423.28
Add 161.15 to both sides:
x = 584.43
The previous balance was $584.43
Answer: Im not too good at math but I will try to help and I will say 70 is the answer...?
Im really sorry if I get this wrong
IF the original number was an integer, then the digit in the ones place of the final product is a zero ( 0 ). If it wasn't an integer, then any digit can be in the ones place.