Q29 of 186 Page 3

Priyanka purchased 2 pencils and 3 erasers for Rs. 9. Sayeeda purchased 1 pencil and two erasers for Rs. 5. Find the cost of one pencil and one eraser.

Let the cost of one pencil = Rs x

and the cost of one eraser = Rs y


According to the question


2x + 3y = 9 …(i)


x + 2y = 5 …(ii)


Now, table for 2x + 3y = 9



Now, table for x + 2y = 5



On plotting points on a graph paper and join them to get a straight line representing 2x + 3y = 9.


Similarly, on plotting the points on the same graph paper and join them to get a straight line representing x + 2y = 5.



∴ x = 3, y = 1 is the solution of the pair of linear equations.


Hence, the cost of one pencil is Rs 3 and cost of one eraser is Rs 1.


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