+0

-3
220
9 Apr 25, 2019

#3
+2

First one   Geometric   ratio , r = 1/5        change 1 to -15   to make arithmetic with  d = -20

You try the next one......or four..... Apr 25, 2019
#4
+2

Second one    arithmetic   with d = -6      change 13 to 14.44    make it geometric with r = .76

Apr 25, 2019
#6
+2

1.  25, 5 , 1        geometric.....  an  =  25(1/5)(n - 1)

2.  25, 19, 13.....arithmetic.....an  = 25 - 6(n - 1)  =  31 - 6n

3.    4, 9 , 16  .......neither..  we have no common difference or common ratio...but if we changed it to   4, 10, 16.....then arithmetic ....an  = 4 + 6(n - 1) =   -2 + 6n

4.   50, 60, 70   ......arithmetic.....an  =  50 + 10(n - 1)  = 40 + 10n

5.  1/2, 3, 18   .....geometric.......an  = (1/2)(6)^(n - 1)   Apr 25, 2019
#7
+1

Please solve the whole problem fully Apr 26, 2019
#8
-3

Arithmetic sequences always have the same common difference (d), each number changes by the same value

Geometric sequences have a common ratio (r). The common ratio is multiplied to every number to get the next

Neither, I am assuming that you mean that the sequence has no common ratio or difference.

Apr 26, 2019
#9
-3

Arithmetic sequences always have the same common difference (d), each number changes by the same value

Geometric sequences have a common ratio (r). The common ratio is multiplied to every number to get the next

Neither, I am assuming that you mean that the sequence has no common ratio or difference.

(Whoops posted that twice)

You can always use these rules for each sequence to figure out which one is which.

Apr 26, 2019
edited by doorknoob  Apr 26, 2019