No 6/7 aja pakai cara ya :D (disederhanakan)

6. 1 ¼+ 1 ⅔ + 2 ⅓ = 5/2 + 5/3 + 7/3 = 15/6 + 10/6 + 14/6 = 39/6 = 13/2 = 6 ½
7. 3 ½ + 5 ³/7 + 2 ⅓ = 7/2 + 38/7 + 7/3 = 147/42 + 228/42 + 98/42 = 473/42 = 11 11/42