72/3 would give you the degree measurement of each slice. take the whole pie (360°) and divide it by the measurement of each piece, and it will tell you how many pieces he cut it in to
Sam cut the pie into 15 equal slices. Each slice has an angle measure of 24 degrees, and together, the remaining 3 slices measure 72 degrees. By dividing the total pie angle (360 degrees) by the angle of one slice (24 degrees), we find the total number of slices.
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