N fair coins are flipped once. The probability that at most 2 of the coins show up as heads is `1/2`.Find the value of N.

Three coins are tossed once. Find the probability of getting at most two heads.

Three fair coins are tossed. Find the probability that they are all tails, if one of the coins shows a tail.

Three coins are tossed once. Find the probability of getting at least one head.

A bag contains 2n+1 coins.It is know that nn of these coins have a head on both of its sides.Whereas the rest of the coins asew fair . A coin is picked up fat random from the bag and is tossed.If the probablity that the toss results in head is (31)/(42) .find the value of n

A bag contains n+1 coins.If is known that one of these coins shows heads on both sides, whereas the other coins are fair.One coin is selected at random and tossed.If the probability that toss results in heads is 7/12, then find the value of n.

A bag contains n+1 coins, one of which is a two heads coin and the rest are fair. A coin is selected at random and tossed. If the probability. That the toss result in a head is 7/12 then the value of n is