Which number comes next in this series: 154, 77, 81, 78, 39, 43, 40, ?

4 Answers

• /2, +4, -3, repeat. 20 is next.

• 20

  since this series consist of 3 nos i.e x , x+4,x+1

  and the next sereis is generated by subtracting x-1 from the first no of series i.e x

  so 39-(x-1)=x

  39-x+1=x

  x=20

  so next series will be 20,24,21 ……..

• yup, as above

• /2, +4, -3

  so answer is 20…………………