A middle school teacher asks students to toss a fair coin 10 times and record their observations as: Number of times head comesNumber of times the coin is tossed and Number of times tails comesNumber of times the coin is tossed She then asks the students to toss the coin 20 times and record their observations in the same way. She continues to increase the number of tosses and asks the students to record their observations. The primary purpose of this activity is to:

A box contains 'x + 4' red, 'x – 1' green and 'x – 5' blue balls. If two balls are drawn from the bag one after another without replacement, then the probability of getting one red and one green ball is equal to the probability of getting a sum equal to or more than 8 when two fair dice are rolled. Find the probability of drawing a red ball when one ball is drawn at random from the bag.

Four persons are chosen at random from a group containing 3 men, 2 women, and 4 children. The probability that exactly two of them are children is: