The probability that at least one of the sides of the triangle is also a side of the octagon is 5/7
A regular octagon has 8 sides, and a triangle has 3 sides
Assume that there is a point on the triangle.
Then we select (3 - 1) points from the (8 - 1) sides.
8 - 1 = 7
3 - 1 = 2
So, the total number of selection is:
Selection = 7C2
Evaluate the combination expression
Selection = 21
Adjacent triangles have 5 lines (one line in common).
So, we have:'
n = 5 - 1
n = 4
The number of ways this points can be selected is:
Selection = 4C2
Evaluate
Selection = 6
The probability that the triangle and the octagon do noth have the same side is:
P= 6/21
The probability that at least one of the sides of the triangle is also a side of the octagon is calculated using the following complement rule
P = 1 - 6/21
Evaluate the difference
P = (21 -6)/21
P = 15/21
Reduce fraction
P = 5/7
Hence, the probability that at least one of the sides of the triangle is also a side of the octagon is 5/7
Read more about probability at:
https://brainly.com/question/251701
