Answer:
f(6) = 25
Explanation:
using the recursive formula with f(1) = 10
note that f(n - 1) is the term preceding f(n)
f(1) = 10
f(2) = f(1) + 3 = 10 + 3 = 13
f(3) = f(2) + 3 = 13 + 3 = 16
f(4) = f(3) + 3 = 16 + 3 = 19
f(5) = f(4) + 3 = 19 + 3 = 22
f(6) = f(5) + 3 = 22 + 3 = 25