Answer: $7 change remains
Step-by-step explanation: When doing rounding in word problems, in most situations you will have to round up regardless of numbers. Rounding to the nickel then means that the cents on the cash amounts must be .00 or .05 Following this pattern:
0.87 is rounded to 0.90
2.66 is rounded to 2.70
3.90 is rounded to 3.90
1.63 is rounded to 1.65
2.53 is rounded to 2.55
1.30 is rounded to 1.30
Then just add together the rounded amounts, which is $13
Simply subtract with the formula, 20-13=7