One is asked to say a two-digit number. What is the probability of it being a perfect square?

A box contains 6 black and 4 white balls. If a ball is taken from it, what is the probability of it being black? And the probability of it being white?

There are 3 red balls and 7 green balls in a bag, 8 red and 7 green balls in another.

i) What is the probability of getting a red ball from the first bag?

ii) From the second bag?

iii) If all the balls are put in a single bag, what is the probability of getting a red ball from it?

Number from 1 to 50 are written on slips of paper and put in a box. A slip is to be drawn from it; but before doing so, one must make a guess about the number: either prime number or a multiple of five. Which is the better guess? Why?

A bag contains 3 red beads and 7 green beads. Another contains one red and one green more. The probability of getting a red from which bag is more?