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