Question

A lending library has a fixed charge for the first three days and an additional charge for each day thereafter. Saritha paid Rs 27 for a book kept for seven days, while Susy paid Rs 21 for the book she kept for five days. Find the fixed charge and the charge for each extra day.​

Answer 1

Solution :

Let fixed charge for 3 days = Rs x

And additional charge = Rs y

According to given condition, we have

x + 4y = 27 ....... (1)

x + 2y = 21 ….... (2)

Subtracting (2) from (1), we get

2y = 6

⇒ y = 6/2

⇒ y = 3

Putting value of y in (1), we get

x + 4 (3) = 27

⇒ x + 12 = 27

⇒x = 27 - 12

⇒x = 15

Therefore, fixed charge for 3 days is ₹ 15 and additional charge for each day after 3 days is ₹ 3.

Answer 2

Let the fixed charge for the first three days be Rs. A and let the charge for each day extra be Rs. B.

According to the information given,

A + 4B = 27 ………. (i)

A + 2B = 21 ……….. (ii)

When equation (ii) is subtracted from equation (i), we get;

2B = 6

B = 3 …………(iii)

Substituting B = 3 in equation (i) we get;

A + 12 = 27

A = 15

Hence, The fixed charge is Rs. 15.

And the Additional charge per day is Rs. 3.

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