Posted by **Anonymous** on Thursday, September 9, 2010 at 12:30pm.

A container has three white balls and two red balls. A first ball is drawn at random and not replaces. Then a second ball is drawn. give the following conditions. What is the probability that the second ball was red? The first ball was white? The first ball was red?

- math -
**MathMate**, Thursday, September 9, 2010 at 1:27pm
1. First ball was red

No. of red balls: 2

Total number of balls:5

P(R)=2/5

2. First ball was white

No. of white balls: 3

Total number of balls: 5

P(W)=3/5

3. Second ball was red:

The probability is given by

P(R,R)+P(W,R)

Now we'll calculate P(R,R)

P(R)=2/5

After the first red, there is one more red left, and four balls altogether, therefore

P(RR)=(2/5)*(1/4)

=1/10

Similarly,

P(WR)=(3/5)*(2/4)

=3/10

Probability of the second ball being red is

(1/10)+(3/10)

=2/5

## Answer this Question

## Related Questions

- Math - A bag contains 5 red balls and 4 white balls. Two balls are drawn at ...
- Math - A bag contains 5red balls and 4 white balls. Two balls are drawn at ...
- math - A box contains three white balls and two red balls. A ball is drawn at ...
- MATH(STATISTICS) - Urn A contains R red balls and W white balls, urn B contains ...
- Math - "In vase A, there are 3 red balls and 5 white balls. In vase B, there are...
- Math - A box contains 2 white calls and 7 pink balls. Two balls are drawn at ...
- math - a. A box contains three white balls and two red balls. A ball is drawn at...
- statistics - An Urn contains 7 red and 3 white balls. Two balls are drawn in ...
- MATH - Urn A contains six white balls and three black balls. Urn B contains ...
- pshs - three balls are drawn successively from a box containing 6 red balls,...