In the two numerical sequences below, one number that appears in the top sequence should appear in the bottom sequence and vice versa. Which two numbers should be changes round? 10, 20, 31, 43, 54, 70. 10, 18, 28, 40, 56, 70.

20 and 18 should be swapped round

54 and 56 should be swapped round

31 and 28 should be swapped round

43 and 40 should be swapped round

10, 20, 31, 43, 54, 70.

10, 18, 28, 40, 56, 70.

10 + 8 = 18

18 + 10 = 28

28 + 12 = 40

40 + 14 = 54

54 + 16 = 70