First thing you need to do is turn the denominators into the same denominators, which would be 28 so we have
16 / 28 + 21 / 28 now add which would be 37 /28 now add 5 + 3 = 8 now divide 37 /28 = [tex]1\frac{9}{28}[/tex] add the 1 to 8 + 1 =9 so our answer is
[tex]9\frac{9}{28} [/tex]