In the arithmetic sequence t1, t2, t3, .... tn, .... t1 = 23 and tn = (tn-1) - 3 for each n>1. What is the value of n when tn = -4?
1) -1
2) 7
3) 10
4) 14
5)20
QA is 10
1) -1
2) 7
3) 10
4) 14
5)20
QA is 10
Ooops! Please move this question to PS.
Anywayz, tn = (tn-1) - 3 and n = 1 , tn = 23.
For such a small series , we can count. Thus, the series is 23, 20, 17, 14, 11, 8,5,2,-1,-4 , basically subtracting a -3 from the previous term. So -4 is the 10th term .
