Respuesta :

19camba

For the answer to the question above, I'll show the solution to my answer below.

a2 = a1 * r 
a2 = 10 * .5 = 5 
a3 = a2 * r 
a3 = 5 * .5 = 2.5 
a4 = a3 * r 
a4 = 2.5 * .5 = 1.25 
So the answer to your problem is
1.25

I hope my answer helped you.