Question

Three coins are tossed simultaneously , what is the probability of obtaining :

1) no heads
2) less then three tails
3) more than one head
4) atleast one tail
5) at most three heads

Answer 1

I think at most three heads

Answer 2

The combinations possible are
H H H
H H T
H T H
H T T
T H H
T H T
T T H
T T T
That is 8 possible outcomes.
1) Out of the 8 possible only TTT fits, so 1/8 = 12.5% probability.
2) Out of the 8 possibleall except TTT fit, so 7/8 = 87.5% probability
3) Only HHH, HHT, HTH, or THH is correct so 4/8 = 50% probability
4)All except HHH fit, so 7/8 = 87.5% probability
5)All fit as no case has more than 3 heads, so 8/8 = 100% probability