What is one ninth plus two thirds simplified

7/9. 1/9 plus 2/3. You have to get the lest common denominator, so change 3 to 9 by multiplying it by three. Remember, you have to do the same thing you do to the denominator to the numerator. So, 2/3 would be 6/9. 6/9 plus 1/9 is easy, basic facts. 1 and 6 is 7, and you put the nine under. You get 7/9

1/9 + 2/3 = 1/9 + 6/9 = 7/9