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Answer:
100 kilometers
Step-by-step explanation:
In order to answer this question, we are going to have to do some multiplication, division, and conversion! To get started, we have to multiply 20 cm by 500,000 to expand the distance to full-scale:
20 * 500,000 = 10,000,000
This is how many centimeters (cm) are between the towns. Now, we have to convert this into kilometers (km). There are 100,000 centimeters in a kilometer, so to convert we have to divide 10,000,000 cm by 100,000:
10,000,000 / 100,000 = 100
Our answer is 100 kilometers.
Hope this helps! :)