Prove that the sum of above written series is (1+2x)/(1+x+x^2)

Weight of Ti=0.75 x 48=36 &wt of oxygen=16

Total weight of TiO=36+16=52
16
Minimum value of percent by weight of oxygen=------- x 100=30.76
52
Weight of Ti=0.69 x 48=33.12& wt of oxygen=16

Total weight of TiO=33.12 + 16= 49.12

16
Maximum value of percent by weight of oxygen=-------- x 100=32.57

49.12

Remaining part of this problem can be solved by above method.