SOLUTION: 61st term of the sequence if a↓4=8 and a↓21=26? 73rd term of the sequence if a↓1=18 and a↓18=52?

Algebra ->  Sequences-and-series -> SOLUTION: 61st term of the sequence if a↓4=8 and a↓21=26? 73rd term of the sequence if a↓1=18 and a↓18=52?      Log On


   

Question 1085358: 61st term of the sequence if a↓4=8 and a↓21=26?
73rd term of the sequence if a↓1=18 and a↓18=52?
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
I'll do one, you do the next.
1.a%5B4%5D=a%5B1%5D%2B%284-1%29d=a%5B1%5D%2B3d=8
2.a%5B21%5D=a%5B1%5D%2B%2821-1%29d=a%5B1%5D%2B20d=26
Subtracting,
a%5B1%5D%2B20d-a%5B1%5D-3d=26-8
17d=18
d=18%2F17
and
a%5B1%5D%2B3%2818%2F17%29=8
a%5B1%5D=136%2F17-54%2F17
a%5B1%5D=82%2F17
.
.
So then,
a%5B61%5D=82%2F17%2B%2861-1%29%2818%2F17%29
a%5B61%5D=82%2F17%2B1080%2F17
a%5B61%5D=1162%2F17
.
.
.
Do the next one the same way.