betsy goes running 2 days out of 7 and james goes running 5 days out of 7. What is the probability that one of them is running on any given day.
not a good question
Betsy could be running the 2 days that James is not running, so one of them would be running every day
in that case the prob = 1
On the other hand , there would have to be days when they are both running or days when only 1 is running, or days when neither is running
The question cannot be answered with the information given.
Multiply the two probabilities together.
2 5 10
- x - = --
7 7 49
There is a 10/49 chance that AT LEAST one of them is running on a given day. I think.
Disregard my previous answer. You should add the probabilities. 7/7 chance.
There is a 10/49 chance that BOTH of them are running.
I am sorry i am confused? Is it 10/49 or is the answer 7/7?
rgrggr
To find the probability that either Betsy or James is running on any given day, we can use the concept of union in probability. The union of two events A and B, denoted by A ∪ B, represents the event that either A or B or both occur.
In this case, the probability of Betsy running on a given day is 2/7, and the probability of James running on a given day is 5/7.
To calculate the probability that either Betsy or James is running on a given day, we can add their individual probabilities and subtract the probability of both events happening together (since we don't want to count it twice):
P(Betsy ∪ James) = P(Betsy) + P(James) - P(Betsy ∩ James)
P(Betsy ∩ James) is the probability that both Betsy and James are running on the same day. Since Betsy goes running 2 days out of 7 and James goes running 5 days out of 7, the probability of both of them running on a given day is (2/7) * (5/7) = 10/49.
Therefore, the probability that either Betsy or James is running on any given day is:
P(Betsy ∪ James) = P(Betsy) + P(James) - P(Betsy ∩ James)
= 2/7 + 5/7 - 10/49
= 35/49 + 35/49 - 10/49
= 60/49
≈ 1.224
So, the probability that either Betsy or James is running on any given day is approximately 1.224 or about 122.4%.