<h2>Answer:</h2>
<u>Every 18 feet.</u>
<h2>Step-by-step explanation:</h2><h3>1. Find the LCM between the numbers.</h3>LCM stands for "least common multiple", and is the least number that results from multiplicating any of the 3 numbers by another number.
Analyze numbers starting from 9 to find the LCM. The first number than can be divided by 3, 6, and 9 is 18. Hence, 18 is out LCM
<h3>2. Interpret the results.</h3>18 as a LCM means that every 18 feet there will be lights at the same distance in the circular road.
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Check out the attched image to see a linear graphic representation of the problem.