Question
The cost of 3 notebooks and 2 erasers is Rs.47, and the
cost of 5 notebooks and 4 erasers is Rs.83. What is the total price (in Rs) of 2 notebooks and 3 erasers?Solution
let the price of one notebook = x and the price of one eraser = y ATQ- 3x + 2y = 47 .... (1) 5x +4y = 83 ......(2) Eq (1) multiplied by 2 6x +4y = 94 … (3) Now subtract Equation (2) from Equation (3): 6x-5x = 94-83 x = 11 put the value of x in eq (1) y =7 now price of 2 notebook + 3 erasers =2× 11+3×7= 43
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