Answer:
Rs.1080
Step-by-step explanation:
1 book=720/6=120
9 books=120*9=1080
You are incorrect the answer is 3 1/4
f(1) = 3
f(n) = f(n-1) - 1
Otherwise,
f(n) = f(1) - (n-1)
=> f(6) = 3 - 5 = -2
Hope this helps!
:)