## A Regular SeriesSeries teasers are where you try to complete the sequence of a series of letters, numbers or objects.
What number comes next in this series? The decimals are rounded to 4 places.
60, 90, 108, 120, 128.5714, 135, 140, 144, 147.2727, ? Bonus What do these numbers represent? ## AnswerThe next number is 150.The formula is 180(n-2)/n, starting with n=3 for the first term. 180*1/3=60 180*2/4=90 180*3/5=108 180*4/6=120 ... 180*10/12=150 Bonus These numbers are the size (in degrees) of the interior angles in a regular n-sided polygon. An equilateral triangle has three 60 degree angles, a square has four 90 degree angles, a regular pentagon has five 108 degree angles, and so on. A regular dodecagon has twelve 150 degree angles. Hide ## What Next?
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