Q18 of 62 Page 121

An alloy contains 40% copper, 32% nickel and rest zinc. Find the mass of zinc in one kg of the alloy.

Given,


Percentage of copper = 40%


Percentage of nickel = 32%


∴ Percentage of zinc = {100 – (40 + 32)} %


= 28 %


Now,


Mass of zinc in 1 kg of the alloy = (28 × 1/100) kg


= 0.28 kg


= 0.28 × 1000 g


= 280 g


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