A lending library has a fixed charge for the first three days and an additional chargefor each day thereafter. Aarushi paid Rs 27 for a book kept for seven days. If fixed charges are Rs `x` and per day charges are Rs `y`. Write the linear equation representing the abvoe information.

Explanation

Given that, a library has a fixed per day charge for the first three days and an additional charge for each day thereafter. The fixed charges are Rs. 'x' per day and the additional charges are Rs. 'y' per day. Also, Aarushi paid Rs. '27' for a book she kept for '7' days.
Since the book was kept for '7' days, fixed charges will be applicable for each of the first three days and an additional charge of Rs. 'y' per day for the remaining days.
Hence, per day charges after three days =Rs. '(x+y)'.

∴ `3x+(7−3)(x+y)=27`

⇒`3x+4x+4y=27`
⇒`7x+4y=27`
Hence, the linear equation representing the given information is `7x+4y=27`