Question

A coin contains 9 grams of nickel and 16 grams of copper, for a total weight of 25 grams. What percentage of the metal in the coin is copper

Answer 1

Explanation:

nickel is 9 grams out of (9 + 16) = 25 grams by weight

9 is what percent of 25?

9 / 25 * 100% = 36%

Answer 2

Explanation:

A coin of 25 grams contains 16 grams of copper.

Then a coin hundred grams contains (100×16)/25 = 64 grams of copper.

Hence the percentage of copper in the coin is 64%.

*I hope that this answer will help you.