Air is 825 times lighter than water and mercury is 13.6 times heavier than water. How many times is mercury heavier than air.

We denote the mass of water by x.

Then the mass of air is x / 825, and the mass of mercury is 13.6 x.

To find out how many times the mercury is heavier than air, you need to divide the mass of mercury by the mass of air.

We represent the decimal fraction 13.6 as a mixed number, that is, a number written as a whole part and a regular fraction: 13.6 = 13 6/10.

Further, we represent the mixed number 13 6/10 as an irregular fraction: 13 6/10 = 136/10.

Decision:

136x / 10: (x / 825) = 136x / 10 (825 / x) = 68 165 = 11 220 (times).

Answer: mercury is 11,220 times heavier than air.