1/4 if they are tossed only once.
The probability of getting two tails in the first two is 1/4. And it does not matter how many more times the coins are tossed after the first two tosses.
If they are fair coins, the probability is 0.25
The probability is 1/4
The probability of 2 coins both landing on heads or both landing on tails is 1/2 because there are 4 possible outcomes. Head, head. Head, tails. Tails, tails. Tails, heads. Tails, heads is different from heads, tails for reasons I am unsure of.
The probability is 3/4.
The probability of tossing a coin twice and getting tails both times is 1 in 4, or 25%. If you have already tossed a coin and had it land on tails, the probability that it will land on tails again the next time you toss it is 50%.
The probability of a fair coin landing on tails is 0.5. The probability of 4 tails is .5*5*.5*.5 = 0.0625.
The probability of getting all tails when you flip 4 fair coins 1 time is:P(4 tails) = (1/2)4 = 1/16 = 0.0625 = 6.25%