Q1 of 71 Page 68

Obtain a pair of linear equations from the following information:

"The rate of tea per kg is seven times the rate of sugar per kg. The total cost of 2 kg tea and 5 kg sugar is Rs. 570."

Let the rate of tea per kg be Rs x and the rate of sugar per kg be Rs y.


According to the question,


x = 7y


⇒ x – 7y = 0 … (i)


Also, cost of 2 kg of tea = 2x and cost of 5 kg of sugar = 5y


⇒ 2x + 5y = 570 … (ii)


Hence, equation (i) and (ii) is the required pair of linear equation.


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