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A model of a ship is made to a scale of 3:400

The surface area of the model is 7200 cm²
Calculate, in m², the surface area of the ship.

1 Answer

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Answer:

Given:

Model : Ship = 3 : 400

The surface area of the model = 7200 cm²

To Find:

The surface area of the actual ship in m²

Let's start with the map scale given:

Model : Ship = 3 : 400

We start by adding in a unit. Usually, we choose the units associated with the model:

Model : Ship = 3 cm : 400 cm

Now, according to tot the question, we know that the actual ship is in m:

Model : Ship = 3 cm : 400 ÷ 100 m

Model : Ship = 3 cm : 4 m

The question asked for surface area, so the units have to be in squares:

Model : Ship = (3 cm)² : (4 m)

Model : Ship = 9 cm² : 16 m²

Now, that we have the units set correctly according to the question requirement, we will find 1 branch of the model:

Model : Ship = 9 cm² : 16 m²

Model : Ship = 9÷9 cm² : 16÷9 m²

Model : Ship = 1 cm² : 16/9 m²

Finally, we can find the required units by multiplying both sides with the required units:

Model : Ship = 1 cm² : 16/9 m²

Model : Ship = 1 x 7200 cm² : 16/9 x 7200 m²

Model : Ship = 7200 cm² : 12800 m²

Answer: The surface area of the ship is 12800 m²

(by the way, this was copied from the same website)

hope this helps :)

User Tim Wakeham
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