Andrea has 6 blue shirts, 2 red shirts, and 5 green shirts in her closet. What is the probability that she will randomly pick out a red shirt on Monday and a green shirt on Tuesday after putting the red shirt in the laundry?
A. 7/25
B. 5/78
C. 7/156
D. 2/5
prob = (2/15)(5/12)
= ...
I think I like (2/13)(5/12)
Dang Siris!
I know, I know,
6+2+5 ≠ 15, but maybe in the far distant past it was.
That's what happens when you have to switch to the second hand to count, I always get confused if I have to count a finger as a carry.
To find the probability, we need to calculate the ratios of the desired outcomes to the total number of outcomes.
First, let's determine the total number of shirts Andrea has:
- Blue shirts: 6
- Red shirts: 2
- Green shirts: 5
The total number of shirts is found by adding these together: 6 + 2 + 5 = 13
On Monday, Andrea puts the red shirt in the laundry, so she is left with:
- Blue shirts: 6
- Red shirts: 1
- Green shirts: 5
To find the probability of drawing a red shirt on Monday, we determine the ratio of red shirts to the total number of shirts:
Probability of drawing a red shirt on Monday = 1/13
On Tuesday, Andrea does not have a red shirt, so she only has blue and green shirts to choose from:
- Blue shirts: 6
- Red shirts: 0
- Green shirts: 5
To find the probability of drawing a green shirt on Tuesday, we determine the ratio of green shirts to the total number of shirts:
Probability of drawing a green shirt on Tuesday = 5/11
Now, we need to find the probability of both events happening, which is calculated by multiplying their individual probabilities:
Probability of picking a red shirt on Monday AND a green shirt on Tuesday = (1/13) * (5/11) = 5/143
However, the red shirt is already in the laundry on Monday, so the denominator should be adjusted to exclude the red shirt. Therefore, the adjusted total number of shirts on Monday is 13 - 1 = 12.
Adjusted probability of picking a green shirt on Tuesday = (1/12) * (5/11) = 5/132
The correct answer is not listed among the options.