Answer:
f(1) = 31.
Step-by-step explanation:
f(n + 1) = f(n) - 3
So f(4) = f(3) - 3
22 = f(3) - 3
f(3) = 22 + 3 = 25
so f(2) = 25 + 3 = 28
and f(1) = 28 + 3 = 31.
