new problem......lots of trouble with probability!!!!!!!!!

[Molly]

a four sided die and a six sided die are thrown. What is the probablity of throwing a difference of one( what does that mean?)...
When i did it I got seven?????

 

[happy]

a difference of one? Is that the complete problem? :?

 

[pka]

A regular tetrahedron is a solid with four faces each of which is an equilateral triangle. That is your four-sided die. Tossed with a regular die there are 24 ordered pair outcomes.
(1,1), (1,2), (1,3), (1,4), (1,5), (1,6)
(2,1), (2,2), (2,3), (2,4), (2,5), (2,6)
(3,1), (3,2), (3,3), (3,4), (3,5), (3,6)
(4,1), (4,2), (4,3), (4,4), (4,5), (4,6).

Use these pairs to count the required events.

 

[stapel]

Re: new problem......lots of trouble with probability!!!!!!!

...a difference of one( what does that mean?)

The two numbers are different by 1, such as 2 and 3, or 5 and 6.

Eliz.

 

[Molly]

Re: new problem......lots of trouble with probability!!!!!!!

a four sided die and a six sided die are thrown. What is the probablity of throwing a difference of one( what does that mean?)...

, and yes...that's the full probelm

 

[pka]

Differ by one. Here are some pairs that meet that required outcome.
(1,2), (2,1), (4,5) & (3,2).
How many in all are there?

 

[soroban]

Re: new problem......lots of trouble with probability!!!!!!!

Hello, Molly!

There must be more to the problem, but I'll take a guess.
$\displaystyle \;\;$(From your answer of "7", I assume you made the same guess.)

A four-sided die and a six-sided die are thrown.
What is the probablity of throwing a difference of one?

The four-sided die has faces marked {1,2,3,4}.
The six-sided die has faces marked {1,2,3,4,5,6}.
$\displaystyle \;\;$Both dice are rolled and their numbers are noted.
What is the probability that the two numbers differ by one?

There are $\displaystyle 4\,\times\,6\:=\:24$ possible outcomes.

There are <u>seven</u> outcomes with a difference of one.
$\displaystyle \;\;(\text{four, six})\;=\; (1,2),\,(2,3),\,(3,4),\,(4,5)\,(2,1),\,(3,2)\,(4,3)$

Therefore: $\displaystyle \,P(\text{diff. of one}) \;= \;\frac{7}{24}$