Question

A lending library has fixed charge for the first three days and an additional charge for each day thereafter. Mona paid ₹27 for a book kept for 7 days, while Tanvy paid ₹21 for the book she kept for 5 days find the fixed charge and the charge for each extra day

Answer 1

Let the fixed charge be Rs.x and the charge for each extra day be Rs.y.
In case of Mona, as per the question
x + 4y = 27             ………(i)
In case of Tanvy, as per the question
x + 2y = 21            ………(ii)
Subtracting (ii) from (i), we get
2y = 6 ⇒ y = 3
Now, putting y = 3 in (ii), we have
x + 2 × 3 = 21
⇒ x = 21 – 6 = 15
Hence, the fixed charge be Rs.15 and the charge for each extra day is Rs.3.