Posted by Kim on .
Please find the next THREE numbers in the patterns and explain how you got them:
1) 5, 5/2, 5/4, 5/8, 5/16....
2) 1, 3, 9, 27, 81...
3) 1/2, 1/2, 3/8, 1/4, 5/32...
4) 9, 101, 999, 10001, 99999...

Math 
Reiny,
1. each new number is 1/2 times the previous one ..
2. How about (3)^n , were n = 0,1,2,3,...
3. What if I rewrote you fractions as
1/2 , 2/4, 3/8 , 4/16, 5/32 ...
Can you see what is happening ?
4. the oddposition numbers are all negative and contain as many 9's as the position in the sequence
e.g. the 7h number would be 9999999 (7 nines)
the evenposition numbers are all positive and start and end with 1, with one less 0 between them as then position of the number
e.g. the 6th number is 1000001 (five 0's between the 1's)