There are 100 pieces of string in my pocket. Each one is between 10 and 20 cm long. If I pull out 30 at random and lay them end to end, what is the probability that the resulting length of string would be more than 480 cm long?

According to modern science, earth is about 4.5 billion years old and written human history extends back about 10,000 years. suppose the entire history of earth is represented with a 10-meter-long timeline, with the birth of earth on one end and today at the other end.

How do you solve a question like this?

The center of the circumscribed circle lies on line segment and the longest side of the triangle is equal to the of the circle.