Probabllity & Statistics

A box has 6 black, 4 red, 2 white and 3 blue shirts. What is probability of picking at least 1 red shirt in 4 shirts that are randomly picked?

Two dice are thrown simultaneously. What is the probability of obtaining a total score less than 10?

The probability that A speaks truth is 4/5, while this probability for B is 3/4. The probability that they contradict each other when asked to speak on a fact is ______.

A box contains 5 black and 5 red balls. Two balls are randomly picked one after another from the box, without replacement. The probability for both balls being red is

Two dice are thrown. Find the probability that the numbers appeared have a sum 8 if it is known that the second die always exhibits 4.