The mass of the 800gr alloy is 60% zinc. 200gr of zinc was added to the alloy and again alloyed.

The mass of the 800gr alloy is 60% zinc. 200gr of zinc was added to the alloy and again alloyed. What percentage of zinc is in the alloy?

Let’s calculate how much zinc is in the first alloy. Let the entire alloy be 100%. Let’s make the proportion:

800 g – 100%,

x g – 60%.

x = 800 g * 60%: 100% = 480 g.

The first alloy contains 480 g of zinc.

The second alloy now weighs 200g more. Let’s find its mass by adding 800 g 200 g to the mass of the first alloy:

800 g + 200 g = 1000 g.

The mass of the second alloy is 1000 g. The mass of zinc has also changed:

480 g + 200 g = 680 g.

Let’s make the proportion and find out how many percent is 680 g of zinc from 1000 g of the alloy:

1000 g – 100%,

680 g – x%.

x = 680 g * 100%: 1000 g = 68%.

Answer: The new alloy contains 68% zinc.