Sunday

April 20, 2014

April 20, 2014

Posted by **Ron** on Monday, May 16, 2011 at 7:45pm.

A. all four marbles are red

B. more of the marbles are green than red

C. both red and green marbles are present

D. two of the marbles chosen are both labeled 5

- pre-calculus -
**Reiny**, Monday, May 16, 2011 at 8:13pmA) prob (4reds) = (7/12)(6/11)(5/10)(4/9) = 7/99

or

Prob = C(7,4)/C(12,4) = 35/495 = 7/99

B) could be GGGG, GGGR

Prob = C(5,4)/C(12,4) + C(5,3)*C(7,1)/C(12,4

= 5/495 + 70/495 = 75/495 = 5/33

C) can't have all red or all green

prob = 1 - (all red + all green)

number of all green = C(5,4) = 5

so prob = 1 - (7/99 + 5/495) = 91/99

D) both are labelled 5

prob = C(2,2)*C(10,2)/C(10,4) = 45/495 = 1/11

**Related Questions**

Probability - An urn contains 7 red marbles labeled {1,2,3,4,5,6,7} and 5 green ...

Discrete Math - A bag contains 5 red marbles, 4 yellow marbles, 3 green marbles...

probability problem - A box contains 6 green, 8 red, 5 yellow, and 10 blue ...

Math-Probability - Hello, I'm trying to figure out this probability problem. Can...

Mathematics - There are 2 white marbles in urn A and 4 red marbles in urn B . At...

Algebra - Out of jar with 100 marbles, 49 are blue marbles, 7 are green marbles...

Math - A bag of marbles contains only green and red marbles. All of the marbles ...

Probabilities - A jar contains 2 red marbles, 3 green marbles, 4 blue marbles, ...

pre-algebra - a bag contains 5 green marbles 2 white marbles 8 blue marbles 9 ...

Math - Suppose an urn contains 8 red,5 white and 7 blue marbles.a.If 3 marbles ...