John has 8/9 of a gallon of apple cider vinegar. If it takes 1/7 of a gallon of vinegar to make a batch of collard greens, how many batches can john make?

1/7 gallon = 1 batch

[multiply by 7 through]

1 gallon = 7 batches

[multiply by 8/9 through]

8/9 gallon = 7 x 8/9

8/9 gallon = 6 2/9

[Good enough to make 6 batches, not enough to make 7 batches]

So he can make 6 batches of collard green