Answer:
1, 3, 7
Step-by-step explanation:
A rational number can be written as a ratio or fraction.
1) I wasn't able to determine a fraction for what I'm assuming you meant by 0.878787878787 going on and on so it must be irrational
2) 3.624 can be written as 3 78/125
3) The square root of two is irrational
4) 0.6666666 going on and on can be written as 1/3
5) -5.6 can be written as a fraction too
6) 1/3 is already a fraction
7) Pi is irrational
Hope that helps!
