Question

Which no. will replace the question mark? 5 , 12 , 26 , 54 , ?

Answer 1

Answer:

89 is the answer

Explanation:

as difference between each number is a multiple of 7

Answer 2

Answer:

110 is the number

Explanation:

5+7*1=12

12+7*2=26

26+7*4=54

54+7*8=110

hence this system is used here