SOLUTION: What is the next number in this sequence and how do you get it? 1,2,5,10,4,8,20,40,? Thank You

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Question 37242: What is the next number in this sequence and how do you get it?
1,2,5,10,4,8,20,40,?
Thank You

Found 2 solutions by checkley71, AnlytcPhil:
Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
1,2,5,10,4,8,20,40,16,32,80,160 MULTIPLY THE FIRST 4 DIGITS BY 4 THEN THE NEXT 4 DIGITS BY 4, ETC.

Answer by AnlytcPhil(1116) About Me  (Show Source):
You can put this solution on YOUR website!
What is the next number in this sequence and 
how do you get it?

1, 2, 5, 10, 4, 8, 20, 40,? 

The sequence starts with 1
Step#
  1.  To get from 1 to the next number 2, we multiply by 2.
  2.  To get from 2 to the next number 5, we add 3.
  3.  To get from 5 to the next number 10, we multiply by 2.
  4.  To get from 10 to the next number 4, we subtract 6.
  5.  To get from 4 to the next number 8, we multiply by 2.
  6.  To get from 8 to the next number 20, we add 12
  7.  To get from 20 to the next number 40, we multiply by 2.
  8.  ?????????????

Steps 1, 3, 5, and 7 are all "multiply by 2"

Step 2 is "add 3"
Step 4 is "subtract 6"
Step 6 is "add 12"

So looking at that step 8 should be "subtract 24"

So the next term of

1, 2, 5, 10, 4, 8, 20, 40, ?

should be gotten by subtracting 24 from 40, getting 16. 

1, 2, 5, 10, 4, 8, 20, 40, 16

Answer: 16

Edwin
AnlytcPhil@aol.com