How many grams silver is added to 13 grams gold to produce 85% gold alloy?

drbob222 I tried that formula bu I guess it's wrong :(

See the post above. The formula is right but I substituted incorrectly. The way I substituted gave % Ag in Au not the other way around.

To determine how many grams of silver must be added to 13 grams of gold to produce an 85% gold alloy, we need to figure out the amount of gold and silver in the resulting alloy.

Let's assume x grams of silver is added to the 13 grams of gold.

The resulting alloy will have a total mass of 13 + x grams.

Since the desired alloy is 85% gold, we can write the following equation:

(13 grams of gold) / (13 + x grams of alloy) = 85% (or 0.85)

To solve for x, we can cross-multiply and solve the equation:

13 grams of gold = (0.85) * (13 + x grams of alloy)

13 = 0.85 * (13 + x)

Divide both sides of the equation by 0.85:

13 / 0.85 = 13 + x

15.29 ≈ 13 + x

Rearranging the equation:

x ≈ 15.29 - 13

x ≈ 2.29 grams

So, approximately 2.29 grams of silver must be added to 13 grams of gold to produce an 85% gold alloy.