Question

Help?

Answer 1

A 6-sided die is weighted so that the probabilities of rolling a 1, 2, or 3 are equally likely, the probabilities of rolling a 4, 5, or 6 are equally likely, and the probability of rolling a 5 is four times the probability of rolling a 3. What is the probablity that a 2 or a 5 is rolled?

Answer 2

Anyone?

Answer 3

Well, since 4,5,6 are equall likely, and so are 1,2,3 then 1 or 4 being rolled is the same as posibility of 2 or 5 being rolled or 3 or 6. So The probability of 2 or 5 being rolled is 1/3.

Answer 4

But 5 has a four times greater chance of being rolled than a 2

Answer 5

If you put it other way around the possibility of rolling 1 or 2 or 3 is x. The possibility of rolling 4 or 5 or 6 is 4x. So considering that all probabilities have to sum up to 1 as you will always roll one of those six numbers then x+x+x+4x+4x+4x=1 thus x=1/15. So the probabilty of rolling two is 1/15 and rolling 5 is 4/15. So the probability of rolloing two or five is 1/15 +4/15 wchich suming up adds to 5/15 which is 1/3.
It doesnt matter that 5 has a four times greater chance of being rolled than a 2 cause the probaility of rolling 5 or 2 is the same as rolling 1 or 4 , ( same with 3 and 6) since the likeliness of rollling 4 or is the same as rolling 5, and rolling 2 is the same as rolling 1.

Answer 6

Ohhhhhhhh! It's 2 OR 5. Sorry I read the question incorrectly. Thank you!!!