Please help me to answer....
I have 4 coins i throw them all what is the probability that 3 would be heads. 1/? (one has to be on top.....
The clue is that its a whole number
And could you please show your working out thanks.....
2007-01-23 20:59:22 · 7 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
what kind of question is this? what do u mean?
2007-01-23 22:43:59 · answer #1 · answered by Misumi Nagisa fan xD 2 · 0⤊ 2⤋
Lets think about heads as x and tails as y
there are 16 possibilities for the way the coins could land
xxxx
yxxx
xyxx
xxyx
xxxy
yyxx
xyyx
xxyy
yxyx
xyxy
yxxy
yyyx
xyyy
yxyy
yyxy
and yyyy
if you count all of the ones with 3 x
it comes to four so
4/16 = 1/4
the easy way to figure it out is
each coin has a 1/2 probability so you multiply 1/2 by 1/2 by 1/2 by 1/2 it equals 1/16 so you know there are 16 possibilities and jst count how many ways there are 3 heads and you come up with 4 tada
I hope this helps
2007-01-23 21:14:41 · answer #2 · answered by karruttopp 2 · 1⤊ 0⤋
Lets solve using the binary counting system!. If we count the numbers from 0 to 15 in binary we have the following
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
If we assume 0 = Heads and 1 = Tails then we have the following
HHHH
HHHT
HHTH
HHTT
HTHH
HTHT
HTTH
HTTT
THHH
THHT
THTH
THTT
TTHH
TTHT
TTTH
TTTT
If we count the number of possibilty with 3 Heads we have the following
HHHT
HHTH
HTHH
THHH
So we have 4 with 3 heads out of 16 possible combinations = 1/4.
2007-01-23 22:13:18 · answer #3 · answered by Joe H 2 · 1⤊ 1⤋
Total arrangements = 2^4 = 16
With just 1 tail there are only 4 configurations
THHH, HTHH, HHTH and HHHT.
So you have
favourable cases / total cases = 4 / 16 = 1/4
2007-01-23 21:10:16 · answer #4 · answered by Jano 5 · 1⤊ 0⤋
You can have 3 heads in the following ways ...
hhht
hhth
hthh
thhh
There are 16 possibilities in all ... you the probability
that you get 3 heads is 4/16.
2007-01-23 21:09:12 · answer #5 · answered by themountainviewguy 4 · 1⤊ 0⤋
12 times 10089 = 121068
2016-03-28 23:58:14 · answer #6 · answered by Anonymous · 0⤊ 0⤋
see my answer in the other question. It's (n!/r!(n-r)!)*(p^r)*((1-p)^(n-r))
2007-01-23 23:42:29 · answer #7 · answered by igorolman 3 · 1⤊ 2⤋