Respuesta :
Complete Question
The sum of 3rd and 4th terms of GP is 108 ,The sum of 4th and 5th term of the same GP is 324 ,find common ratio
Answer:
3
Step-by-step explanation:
The formula for Number of term of a GP = ar^n-1
The sum of 3rd and 4th terms of GP is 108
ar² + ar³ = 108... Equation 1
ar²(1+ r) = 108 ..... Equation 1
The sum of 4th and 5th term of the same GP is 324 ,
ar³ + ar⁴= 324... Equation 2
ar³ (1 + r) = 324..... Equation 2
find common ratio
ar²(1+ r) = 108 ..... Equation 1
ar³ (1 + r) = 324..... Equation 2
Solving for r
ar²(1+ r)/ar³ (1 + r) = 108/324
1/r = 1/3
r = 3
Hence, Common ratio = 3
