11 times as many damselfish as clownfish would mean damselfish = 11 times clownfish. Use variable to represent each fish, so variable c will be used to represent clownfish and variable d with be used to represent damselfish. So from as before, d = 11c . Since there is a total of 36 fish, the equation would look to be about d + c = 36. Since we know that d = 11c, you replace the d with 11c. So it will now look like 11c + c = 36. Add like terms , which will be 11c + c to equal 12c. So the new equation is now 12c = 36. To isolate variable c, divide 12 to both sides to get c = 3 . There are 3 clownfish. To find out how many damselfish, replace 3 with c in the equation for d, which is d = 11c. d = 11(3) . d = 33. There are 33 damselfish and 3 clownfish in the tank.