Question

How do I solve this question

Answer 1

Answer: C

Step-by-step explanation:

S = $\frac{a}{1-r}$

a = 80, r = $-\frac{1}{4}$

S = $\frac{80}{1-(-\frac{1}{4})}$

  = $\frac{80}{\frac{5}{4}}$

  = $\frac{80*4}{5}$

  = 64