Every three days Marco fills up his car with gas. Every eight days he washes his car. On what day will Marco go fill his car with gas and wash it?

24th Day

Step-by-step explanation:

1.) Evaluate Data

Marco washes his car every 8 days. Marco fills his car with gas every 3 days. The question is asking when Marco will wash his car and fill it with gas.

2.) Solve

Find common factors for the two numbers:

3: 3, 6, 9, 12, 15, 18, 21, 24

8: 8, 16, 24

3 and 8 share 24 as a common factor.

3) Conclusion

Since the 3 and 8 share a common factor of 24 Marco will wash his car and fill it with gas every 24th day.