a coin is tossed 3 times , what is the probablity that we gwt heads twice
Let H represent an outcome of heads and T represent an outcome of Tails.
For three tosses of the coin all the possible outcomes are:
H-H-H T-H-H H-T-H H-H-T T-H-T T-T-H H-T-T T-T-T
These eight possible outcomes are the sample space.
To find the probability of tossing heads exactly twice look down the sample space list and find any outcome that has exactly two H's. The possibilities are T-H-H, H-T-H, and H-H-T. This means that three of the eight possible outcomes contain exactly two heads.
Therefore, the probability of throwing exactly two heads in three tosses of the coin is 3 out of 8, or 3/8 or the decimal equivalent of 3/8 which is 0.375 or 37.5 percent.