An alloy of copper, tin and zinc has 32% tin, copper 40 g less than tin, zinc 100 g more

An alloy of copper, tin and zinc has 32% tin, copper 40 g less than tin, zinc 100 g more than copper. Find the mass of the alloy.

Suppose the mass of the alloy is x grams.

According to the condition of the problem, the content of tin in the alloy is 32%, which means that the mass of tin in the alloy is:

x: 100 * 32 = 0.32 * x g.

The mass of copper is 40 g less than the mass of tin, which means it is equal to:

0.32 * x – 40 g.

The mass is 100 g more than the mass of copper, which means it is equal to:

0.32 * x – 40 + 100 = 0.32 * x + 60 g.

Let’s compose and solve the equation:

0.32 * x + 0.32 * x – 40 + 0.32 * x + 60 = x,

0.96 * x + 20 = x,

0.4 * x = 20,

x = 20: 0.4,

x = 50 (g) – mass of tin,

50 – 40 = 10 (g) – the mass of copper,

10 + 60 = 70 (g) is the mass of zinc.

Thus, the mass of the alloy is equal to:

50 + 10 + 70 = 130 (g).