Question

In my fish tank, the ratio of red fish to blue fish is 3:5. There are 20 blue fish. How many red fish are there?

Answer 1

First, the ratio is 3:5. which means 3 redfish for every 5 bluefish. Since there are 20 bluefish, that means that is 4x more than 3:5. The total number of redfish are 12.

Answer 2

red fish : blue fish 
    3       :    5
   (x4)       (x4)
    12     :   20

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Answer : There are 12 red fish.
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