Draw and use a tape diagram to model and solve the problem below.
In a fish tank, the ratio of goldfish to guppies is 2 to 4. There are a total of 12 fish in the fish tank. Determine the number of goldfish in the fish tank.
To draw a tape diagram, we start by drawing a rectangle to represent the total number of fish in the tank, which is 12. Then, we divide the rectangle into six equal parts, each representing two fish. We label two of these parts as goldfish and four as guppies, according to the given ratio.
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2 2 2 2 2 2
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G G | | | |
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F F F F
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We can see that there are six equal parts in the rectangle, so each part represents two fish. Therefore, the two parts labeled as goldfish represent a total of 4 fish.
Therefore, there are 4 goldfish in the fish tank.