Question

The aquarium has 6 fewer yellow fish than green fish. 40 percent of the fish are yellow. How many green fish are in the aquarium?

Answer 1

Step 1:

Let the number of green fish = m

Therefore, the number of yellow fish = m - 6

Total number of fish = m + m - 6 = 2m - 6

Step 2:

percentage of yellow fish = 40%

Step 3:

$\begin{gathered} 40\text{ of total fish = m - 6} \\ \frac{40}{100}(2m\text{ - 6) = m - 6} \\ 0.4(2m\text{ - 6) = m - 6} \\ 0.8m\text{ - 2.4 = m - 6} \\ \text{6 - 2.4 = m - 0.8m} \\ \text{3}.6\text{ = 0.2m} \\ \text{m = }\frac{3.6}{0.2} \\ m\text{ = 18 gr}een\text{ fish} \end{gathered}$

Final answer

There are 18 green fishes in the aquarium