I'm just guessing but maybe expressions
In an hour, 80 people could ride the ferris wheel. So, that means in 3 hours 240 people could ride it.
Because the ratio for both candles is 20/60 or 1/3 then take the number of ounces the candle has and divide by 1/3. In expression: 9 / 1/3 => 9 * 3 = 18
It means to move something