okay so what you would do is find a number both denominators ( number under fraction line ) would go into. in this case it would be 8, 4 can go into 8 twice and 8 can go into 8 once. you would do 4 times the number to get to 8 which is 2 so 4 x 2= 8, and then what u multiply the denominator by, you multiple the numerator by, 3 x 2 = 6 therefore it would be 6 6/8 and 10 3/8 then 10+6=16+ 6/8 + 3/8 would be 17 1/8... hope this helps :)