Hello there.
Question: The diameter of a circle is 19 inches. Using the formula C ≈ 3d, what is the approximate circumference of the circle?
Answer: The formula is stating that the circumference is approximately equal to 3 times the diameter.
If the diameter is 19 in then to figure out the approximate value of the circumference you need to multiply it by 3.
19 x 3 = 57.
The circumference is approximately 57 in.
Hope This Helps You!
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