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If a road on a map is 12 cm long and represents a scale of 3 cm to 7 km, how long is the road in real life?

a) 4 km
b) 16 km
c) 28 km
d) 84 km

User Dondon Jie
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1 Answer

5 votes

Final answer:

Using the scale provided of 3 cm to 7 km, a road that is 12 cm long on the map corresponds to a real-life distance of 28 km.

Step-by-step explanation:

To calculate the real-life distance represented by the 12 cm road on the map, we can set up a proportion based on the given scale of 3 cm to 7 km. The proportion is as follows:

3 cm : 7 km = 12 cm : X km

To find the value of X, we cross-multiply and solve for X:

(3 cm) × (X km) = (12 cm) × (7 km)

X × 3 cm = 84 cm×km

X = 84 cm×km / 3 cm

X = 28 km

Therefore, the road in real life is 28 km long, which corresponds to answer option (c).

User ToddBFisher
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