The common ratio of a G.P. is 2. If the 5th term is
greater than the 1st term by 45, find the 5th term,
- 3
- 6
- 45
-
48
- 90
The correct answer is: D
Explanation
a = 1st term ; ar4 = 5th term∴ ar4 = a(2)4 = 16a; 16a = 45 + a, a = 3;
3(2)4 = 48