2/9 x 63 = 126/9 = 14.
2/9 + 1/7 = 14/63 + 9/63 = 23/63
63
It is: 7/9 of 63 = 49
63
28
It has to be 7x9 or 63 or less. There is no number less than 63 which is divisible by both 7 and 9 therefore 63 is the LCD.
35.
28
81
56
Good question, I had to think on that a bit. Four ninths is greater than three sevenths.