HELP ME ANSWER THIS

Question

In the video, the water level was 15 milliliters before adding the chain, and 20 milliliters after adding the chain. When I weighed the chain, its mass was 74.4 grams.

I believe the chain is solid metal (not gold plated), but is probably a blend of gold and other metals. I looked up that gold has a density of 19.3 g/ml, while the other metals like silver and copper usually blended with gold have a combined density of about 9.7 g/ml.

Determine what percentage of the chain is gold, by mass, to at least 1 decimal place?

Answer 1

Not really a Trigonometry problem. More of a mixture.

1)

Determine density of chain

74.4 g / 5 ml = 14.88 g/ml

2)

Set up mixture

19.3x + 9.7(74.4 - x) = 14.88(74.4)

19.3x + 721.68 - 9.7x = 1107.072

9.6x = 385.392

x = 40.145

77.4 - x = 37.255

3)'

Determine percentages

Divide x / 74.4 to determine % of gold.