maths probabilities

[troot28]

please help

if four coins are tossed what are the probabilities of:-
getting four heads
getting one head and three tails
getting two heads and two tails
getting at least one tail

[buildersmate]

1) 1 in 16
2) 1 in 4
3) 3 in 8
4) 15 in 16
(I think - someone will be quick to correct me wrong)

[troot28]

Thanks buildersmate.
All of this to help my son with his homework!!
I think your answer is correct providing sequence is ignored. If sequence is important then there are 16 possibilities:-

4 Heads - HHHH
4 Tails - TTTT
3H,1T - HHHT, HTHH, HHTH, THHH
1H,3T - HTTT, THTT, TTHT, TTTH
2H,2T - HHTT, HTHT, HTTH, THHT, THTH,TTHH.

Therefore:-
4 Heads is 1 in 16
1Head & 3 Tails is 1 in 4
2 of each is 3 in 8
At least one tail is 15/16

Now all we gotta do is figure out how to show these possibilities in table form !!!!

[troot28]

Sorry buildersmate - I just realised that your answers are identical to mine. Only took me 2 1/2 hours to work out - so I bow to your superior intellect