Q3 of 25 Page 79

The ratio of weights of copper and zinc in brass is 13:7. Find the weight of zinc in a brass utensil weighing 700 gm.

let the weight of zinc be

copper/zinc = copper/x = 13/7


copper = 13x/7


So according to given conditions


x + 13x/7 = 700


Multiplying both side by 7


7x + 13x = 4900


20x = 4900


Dividing both side by 20


x = 245


So, weight of zinc is 245g


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