We want to find the area of the coin that has a diameter of 30 millimeters.
Remember that the area of a circle with radius r is calculated using the formula below.
A=π r^2
Here, we know that the diameter of the coin is 30mm. To use the formula, we first need to divide the diameter by 2 to determine the radius.
r=30/2= 15
Let's substitute 15 for r in the formula and calculate A. We will use 3.14 for π.
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