Q5 of 40 Page 86

5 pencils and 7 pens together cost D50 whereas 7 pencils and 5 pens together cost D46. Find the cost of one pencil and that of one pen.

Let the cost of one pencil and one pen be ₹x and ₹y respectively.

According to given situation, we have :


5x + 7y = 50


7x + 5y = 46


5x + 7y = 50 7x + 5y = 46





From the graph. It can be observed that the two lines are intersecting each other at (3,5)


x = 3 and y = 5


Cost of pencil = ` 3;


Cost of pen = ` 5


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