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gmatNooB8787
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Problem : At a motivational forum, a group of 1,500 people are separated into two groups, the Leaders and the Followers. 1,000 people are assigned to the Followers and 500 are assigned to the Leaders. Among these people, there are 75 married couples, each consisting of 1 Leader and 1 Follower. If 1 person is chosen randomly from each group, what is the probability that the two people chosen will be a married couple?
{
Is this different from asking : If 1 person is chosen randomly from each group, what are the different ways for choosing such that the two people chosen will be a married couple?
Would the ans be different.
becoz what i initially thought was to calculate individually each way of choosing one spouse and then the other. It gave me the double , since there are two ways , i.e. either u choose the husband or the wife first.
i.e. 75/1,000 × 1/500 + 1/1,000 × 75/500 = 3 / 10000
Please clarify.
}
A. 3/20000
B. 1/4500
C. 19/1800
D. 1/75
E. 1/20
Soln: The solution is that 75/1,000 × 1/500 = 15/1,000 × 1/100 = 15/100,000 = 3/20,000.
{
Is this different from asking : If 1 person is chosen randomly from each group, what are the different ways for choosing such that the two people chosen will be a married couple?
Would the ans be different.
becoz what i initially thought was to calculate individually each way of choosing one spouse and then the other. It gave me the double , since there are two ways , i.e. either u choose the husband or the wife first.
i.e. 75/1,000 × 1/500 + 1/1,000 × 75/500 = 3 / 10000
Please clarify.
}
A. 3/20000
B. 1/4500
C. 19/1800
D. 1/75
E. 1/20
Soln: The solution is that 75/1,000 × 1/500 = 15/1,000 × 1/100 = 15/100,000 = 3/20,000.
