Did i answer correctly?

Find the sum of each infinite geometric series.
14. 4 + 2 + 1 + …
= 8

16. 1 + ½ + ¼ + …
= 2

18. 16 + 1.6 + .16 + …
17.7

1 answer

The first two are correct,
the last one is off
16 + 1.6 + .16 + …
a = 16
r = 1/10
sum of all = a/(1-r) = 16/(1-1/10) = 16/(9/10)
= 160/9
17.7 is the rounded answer to the correct answer of 160/9