An ingot of silver with a mass of 4 kg and a silver content of 90% was melted down by adding 1 kg

An ingot of silver with a mass of 4 kg and a silver content of 90% was melted down by adding 1 kg of silver to it. Determine the percentage of silver in the resulting ingot.

1. Condition: the weight of the ingot is 4 kg, the percentage of silver in it is 90%. Let’s calculate the amount of silver in kilograms:

4 × 0.9 = 3.6 kg

2. A kilogram of pure silver was added to the ingot, hence the mass of silver in the ingot became 3.6 + 1 = 4.6 kg. But the mass of the ingot also increased and became equal to 4 + 1 = 5 kg. Let’s calculate the ratio of silver to the total mass of the ingot:

4.6 / 5 = 0.92

3. Let’s convert the number into percent and write down the answer:

0.92 × 100 = 92%

Answer: the silver content in the resulting ingot is 92%.