There are 3 series, you have to find value of a, b, c and then establish relation among a,b,c.

19, 25, 45, a, 553, 2767

1560 760 360 160 60 b

16 41 116 341 1016 c

Solution

For a: 19 × 1 + 6 = 25 25 × 2 - 5 = 45 45 × 3 + 4 = 139 139 × 4 - 3 = 553 553 × 5 + 2 = 2767 For b: 1560 ÷ 2 – 20 = 760 760 ÷ 2 – 20 = 360 360 ÷ 2 – 20 = 160 160 ÷ 2 – 20 = 60 60 ÷ 2 – 20 = 10 For c: 16 × 3 – 7 = 41 41 × 3 – 7 = 116 116 × 3 – 7 = 341 341 × 3 – 7 = 1016 1016 × 3 – 7 = 3041 For a: 19 × 1 + 6 = 25 25 × 2 - 5 = 45 45 × 3 + 4 = 139 139 × 4 - 3 = 553 553 × 5 + 2 = 2767 For b: 1560 ÷ 2 – 20 = 760 760 ÷ 2 – 20 = 360 360 ÷ 2 – 20 = 160 160 ÷ 2 – 20 = 60 60 ÷ 2 – 20 = 10 For c: 16 × 3 – 7 = 41 41 × 3 – 7 = 116 116 × 3 – 7 = 341 341 × 3 – 7 = 1016 1016 × 3 – 7 = 3041 a > b < c For a: 19 × 1 + 6 = 25 25 × 2 - 5 = 45 45 × 3 + 4 = 139 139 × 4 - 3 = 553 553 × 5 + 2 = 2767 For b: 1560 ÷ 2 – 20 = 760 760 ÷ 2 – 20 = 360 360 ÷ 2 – 20 = 160 160 ÷ 2 – 20 = 60 60 ÷ 2 – 20 = 10 For c: 16 × 3 – 7 = 41 41 × 3 – 7 = 116 116 × 3 – 7 = 341 341 × 3 – 7 = 1016 1016 × 3 – 7 = 3041 a > b < c