-30 is the answer for your question
<h3>
Answer: 6</h3>
Work Shown:
E = exterior angle = 60 degrees
n = number of sides of the regular polygon
n = 360/E
n = 360/60
n = 6
The regular polygon has 6 sides.
Probability ( 1 blue marble and 3 green marbles) = ( Blue, green, green, green) + ( green, blue, green, green) + ( green, green, blue, green) + ( green, green, green, blue) = { (8/13) × (5/12) × (4/11) × (3/10) } + { (5/13) × (8/12) × (4/11) × (3/10) } + { (5/13) × (4/12) × (8/11) × (3/10) } + { (5/13) × (4/12) × (3/11) × (8/10) } = (4/143) + (4/143) + (4/143)+ (4/143) = 16/143
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