Question

In A certain chemical, the ratio of zinc to copper is 3 to 19. A jar of the chemical contains 836 grams of copper. How many grams of zinc does it contain

Answer 1

The jar contains 132 grams of zinc

Explanation:

zinc to copper = 3 : 19

New equivalent weights

zinc to copper = x : 836

Now, let us solve for x as follows

`(zinc)/(copper) = (3)/(19) = (x)/(836) \\\\cross-multiplying\\3 *\ 836 = 19 *\ x\\2508 = 19x\\x = (2508)/(19)\\x = 132`

the jar contains 132 grams of zinc

To check if the answer is accurate, the answer gotten when the weight of zinc is divided by copper will be the same for both the old and new ratios:

old ratio: 3 ÷ 19 = 0.158

new ratio: 132 ÷ 836 = 0.158