Question

If the 4th and 9th terms of a gp be 54 and 13112 respectively, find the gp

Answer 1

questions founds to be incorrect

Answer 2

The general formula for the nth term of a geometric progression is: 
a(n) = ar^(n-1) 

a= first term

r= common ratio

So, the terms of a geometric progression are: 
a, ar, ar², ar^3, ar^4, etc. 

Fourth term: 
ar^3= 54 

Ninth term: 
ar^8= 13112

a
$a_{9} = a_{4}r {}^{(9 - 4)} \\ 13112 = 54r {}^{5} \\ r {}^{5} = 242.814 nearly 243 = > 3 \\ a_{4} = a_{1}(r {}^{4 - 1} ) = 54 \div 3 {}^{3} = 54 \div 27 = 2$