Question

5,9,21,37,81,_ . complete the number series

Answer 1

Hey mate here is ur ans
we can see that the first term is 5
and the second term is first term+4=5+4=9
the third term is first term *4+1=5*4+1=21
the 4th term is the second term*4+1=9*4+1=37

so again the 5th term will resemble with the first term
so the required 6th term =5th term+4=81+4=85

hope it helps you

Answer 2

Answer:

Therefore, The sequence is 5, 9, 21, 37, 81, 153

Step-by-step explanation:

9 is obtained by :

5 × 2 - 1 = 10 - 1 = 9

21 is obtained by :

9 × 2 + 3 = 18 + 3 = 21

37 is obtained by :

21 × 2 - 5 = 42 - 5 = 37

81 is obtained by :

37 × 2 + 7 = 74 + 7 = 81

Similarly, The next number will be obtained by multiplying the previous number by 2 and doing the alternate addition and subtraction of the odd numbers in the increasing order

⇒ Next number = 81 × 2 - 9 = 162 - 9 = 153

Therefore, The sequence is 5, 9, 21, 37, 81, 153