Q6 of 186 Page 4

If the cost of 2 pencils and 3 erasers is Rs. 9 and the cost of 4 pencils and 6 erasers is Rs. 18. Find the cost of each pencil and each eraser.

Let the cost of one pencil = Rs x

and cost of one eraser = Rs y


According to the question


2x + 3y = 9 …(1)


4x + 6y = 18


⇒2(2x + 3y) = 18


⇒2x + 3y = 9 …(2)


As we can see From Eq. (1) and (2)



∴Given pair of linear equations has infinitely many solutions.


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