Question

If the first term of a G.P. is 20 and the common ratio is 4. Find the 5th term.

• A. 1280
• B. 2048
• C. 5120
• D. 2560

Answer 1

Answer:

C. 5120

$a=20, r=4$

$a_n=ar^{n-1}$

$a_5=20\times4^4$

$=20\times256$

$=5120$