Is 5/6 is greater than 10/12

NO. 5/6 is 10/12, since all your doing is multiplying the fraction 5/6 by 2 on both the denominator and the numerator to get 10/12. Since 2 is commonly multiplied, it can be factored out as well, thus leaving 5/6 = 10/12.

The first one, i believe, would be correct. all the others have one thing in common, and that's that they have repeating numbers. in the second one, x and y have repeating 6's and 3's, and in the third, x and y have repeating 6's as well. in the last one, there are repeating 3's. the first one has no repeating numbers.