In a group of persons, 70% of the persons are male and 30% of the persons are married. If two sevenths of males are married, what fraction of the females is single?
- A2/7
- B1/3
- C3/7
- D2/3Correct
Explanation
Let's assume the total number of persons in the group is 100.
-
Males = 70% of 100 = 70
-
Females = 30% of 100 = 30
-
Total married persons = 30% of 100 = 30
-
Married males = (2/7) of total males = (2/7) * 70 = 20
-
Married females = Total married persons - Married males = 30 - 20 = 10
-
Single females = Total females - Married females = 30 - 10 = 20
-
Fraction of females that is single = (Single females) / (Total females) = 20 / 30 = 2/3
Therefore, 2/3 of the females are single.
Option D is correct.
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