(64+72)/8= 64/8+72/8 = 8+9=17
(36+81)/9= 36/9 + 81/9 = 4 + 9 = 13
(63+49)/7 = 63/7 + 49/7 = 9 + 7 =16
(45+35)/5 = 45/5 + 35/5 = 9 + 7 = 16
(54+48)/6 =54/6+48/6 = 9 + 8 =17
(42+70)/7 = 42/7 +70/7 = 6 + 10=16
(72+81)/9 = 72/9 + 81/9 = 8 + 9 =17
(56+32)/8 = 56/8 +32/8 = 7 + 4 =11