Floyd is playing a game where he is trying to roll a 3 with a standard die. If he gets a 3 in any of his first 8 rolls, he wins; otherwise, he loses. What is the probability that Floyd loses the game?

Question

tkhunny · Answer

What is the probability of a 3 an any single roll?
What is the probability of getting NO 3 in 8 rolls?

hockeychick23 · Answer

1/6 in 1 roll and none maybe 1 in 48?

anonymous · Answer

There are 6 posibble options when you roll a die : 1,2,3,4,5 and 6
yes 1/6 that when you roll you will get a 3
5/6 that when you roll you wont get a 3

hockeychick23 · Answer

yepp, so then what do i do with the 8 now that i have the 1/6 and 5/6?

tkhunny · Answer

No guessing.

p(3) = 1/6

p(not 3) = 1-p(3) = 1-(1/6) = 5/6

p(no 3 in 8 rolls) = ????

tkhunny · Answer

Absolutely not.  0 <= p(stuff) <= 1

tkhunny · Answer

Independent events.  Use the multiplication rule.

hockeychick23 · Answer

ok so 1/6*1/6*1/6

anonymous · Answer

dang it that was incorrect ....
$$p^n$$
where p is the probability that you wont roll a 3 and n is the amount of times you can roll the die

hockeychick23 · Answer

got it, 23.3, thanks!

anonymous · Answer

.233 watch your decimals

tkhunny · Answer

Not quite.  Heartbreak had the compliment of the probability of rolling a 3 all eight time.

How may times are we rolling the die?  You seem to have just 3.  And we don't care about rolling 8 3s.  Just one.  Thus, we need to concern ourselves with rolling NO 3s.

p(3) = 1/6

p(not a 3) = 5/6

p(no 3 in 8 tries) = (5/6)^8

Come on!  You're making me do all the work.

hockeychick23 · Answer

sorry i meant 23.3%

anonymous · Answer

Yup thats correct

hockeychick23 · Answer

thankss(: