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Question
An eraser costs Rs. 1.50 less than a sharpener. Also, the cost of 4 erasers and 3 sharpeners is Rs.29. Taking x and y as the costs (in Rs.) of an eraser and a sharpener respectively, write two equations for the above statements and find the value of x and y.
Solution
Cost of an eraser = Rs. x
Cost of a sharpener = Rs. y
According to given information, we have
x = y - 1.50
⇒ x - y = -1.50 ....(i)
And, 4x + 3y = 29 ....(ii)
Multiplying eqn. (i) by 3, we get
3x - 3y = -450 ....(iii)
Adding eqns. (ii) and (iii), we get
7x = 24.50
⇒ x = 3.50
⇒ 3.50 - y = -1.50
⇒ y
= 3.50 + 1.50
= 5
Thus, the cost of an eraser is Rs.3.50 and that of a sharpener is Rs.5.
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