Question

Find a₁ for the given geometric series. Sn = 45450, r = 3.6, n = 6 ?

Answer 1

SN = 45450

r : 3.6

n : 6

so we can use the formula of SN of G.S directly

SN = a( r^n - 1 )/r - 1

45450 = a ( 3.6^6 - 1 ) / 3.6 - 1

45450 = a ( 2176.78 - 1) / 3.6 - 1

Explanation:

45450 × 2.6 = a( 2175.78 )

a = 118170/2175.78

; a = 54.31