Respuesta :

Using proportions, it is found that there are 20 blue fish in the aquarium.

What is a proportion?

A proportion is a fraction of a total amount, and the measures are related using a rule of three.

In this problem, there are:

  • x blue fish.
  • x + 10 red fish.
  • Hence a total of 2x + 10 fish.

x is 40% of 2x + 10, hence:

x = 0.4(2x + 10)

x = 0.8x + 4

0.2x = 4

x = 4/0.2

x = 20.

Hence, there are 20 blue fish in the aquarium.

More can be learned about proportions at https://brainly.com/question/24372153

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