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प्रश्न
Form the pair of linear equation in the following problem, and find its solution (if they exist) by the elimination method:
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.
उत्तर
Let the fixed charge for the first three days and each day charge thereafter be Rs x and Rs y, respectively.
According to the question,
x + 4y = 27 ...(1)
The charge for keeping a book for five days is ₹ 2.
x + 2y = 21 ...(2)
By subtracting equation (2) from equation (1)
(x + 4y = 24) - (x + 2y = 21)
y = 3
Putting the value of y in equation (1)
x = 15
Hence, the fixed charge is ₹ 15 and the charge for the additional day is ₹ 3.
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