Look at this series: 1.5, 2.3, 3.1, 3.9, ... What number should come next?

Look at this series: 14, 28, 20, 40, 32, 64, ... What number should come next?

Look at this series: 201, 202, 204, 207, ... What number should come next?

Look at this series: 544, 509, 474, 439, ... What number should come next?

Look at this series: 80, 10, 70, 15, 60, ... What number should come next?

Look at this series: 2, 6, 18, 54, ... What number should come next?

$ & # $ $ & # # $ ? & ? # $ $ $ &

• * | o o o o | * * ? | o o ? | * * * * | o o |