Teri and her friends bought a party size sandwich that was 7/9 yard long. they ate 2/3 of a yard. what part of the yard was left?

Teri had 7/9 of a sandwich, you need to find a common denominator for 2/3. Multiply 2/3 by 3 which is 6/9. (6/9 is how much they ate) Then you subtract 7/9 by 6/9 (7/9-6/9=1/9)
1/9 of a yard

I hope this helped.. not much of a teacher hahah :)