Final answer:
The Great Wall of China was approximately 3,000 miles long.
Step-by-step explanation:
The Great Wall of China was 10,000 li long. In this case, li is a unit of measure. We are told that 2 li is approximately equal to 0.6 miles. To find how many miles the Great Wall is, we can set up a proportion:
2 li = 0.6 miles
10,000 li = x miles
To solve for x, we can cross multiply and divide:
10,000 li * 0.6 miles = 2 li * x miles
6,000 miles = 2x
x = 6,000 / 2
x = 3,000 miles
Therefore, Shih Huangdi's Great Wall of China was approximately 3,000 miles long.