Respuesta :

MathPhys

Answer:

4

Step-by-step explanation:

The sum of the first n terms of a geometric series is:

S = a₁ (1 − rⁿ) / (1 − r)

Given S = 15624, r = 5, and n = 6:

15624 = a₁ (1 − 5⁶) / (1 − 5)

a₁ = 4