OpenStudy (anonymous):

If six pennies are tossed onto the table, what is the probability of seeing two heads and four tails?

2 years ago
OpenStudy (amistre64):

how many ways can you arrange them?

2 years ago
OpenStudy (amistre64):

\[\binom{n}{r}p^rq^{n-r}\]

2 years ago
OpenStudy (amistre64):

if p=q this amounts to:\[\binom{n}{r}p^n\]

2 years ago
OpenStudy (anonymous):

they're being tossed all at the same time, not one by one

2 years ago
OpenStudy (amistre64):

doesnt really matter

2 years ago
OpenStudy (amistre64):

one by one we can get: t h h t t t or if we throw them all at once t h h t t t

2 years ago
OpenStudy (anonymous):

ok thx i see, so it's 0.234375?

2 years ago
OpenStudy (amistre64):

what is 6 choose 2? the rest is 1/2^6 of course

2 years ago
OpenStudy (amistre64):

15 * 1/2^6 whatever that turns out to be eh

2 years ago
OpenStudy (anonymous):

well as a fraction it'd be 15/64

2 years ago
OpenStudy (amistre64):

yeah, thatll be it

2 years ago
OpenStudy (anonymous):

ah ty that's what i got

2 years ago