Question

9,17,31,57,?,205 What is the answer fill it?

Answer 1

Answer: 105

Step-by-step explanation:

The next number is the sum of the previous 3 numbers  

So:  

If we start with 1,1,1 next one is 1+1+1 = 3  

We have 1,1,1,3 next one is 1+1+3 = 5  

We have: 1,1,1,3,5 next one is 1+3+5 = 9  

We have: 1,1,1,3,5,9 next one is 3+5+9 = 17  

We have: 1,1,1,3,5,9,17 next one is 5+9+17 = 31  

 

We have: 1,1,1,3,5,9,17,31 next one is 9+17+31 = 57  

We have: 1,1,1,3,5,9,17,31,57 next one is 17+31+57 = 105

Answer 2

Answer

here actually the pattern is

1) 9*2-1=17  

2)17*2-3=31 ( number multiply by 2 and substract next odd number )

3)31*2-5=57 ( odd number.... next to 3 is 5)

4)57*2-7=107 ( odd number..... next to 5 is 7)

5)107*2-9= 205 ( odd number....next to 7 is 9 )

hence it is satisfying all the terms and the answer is 107....the right answer