and since we have to state the answer to 2 decimal places, that means that we are using the number value for π. In specific, π = 3.1415 is good enough. The other thing we note is that the formula for circumference could also be written in terms of its diameter as opposed to its radius:
C = πd. Let's use that one since we are given the diameter of the tire, not the radius.
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and in second brackets common is 5:
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