Question

In a group of persons, 70% of the persons are male and 30% of the persons are married. If two-sevenths of the males are married, what fraction of the females is single ?  

(a) 2/7 (b) 1/3 (c) 3/7 (d) 2/3

Answer 1

(d) Let the no. of total persons = 100

∴ No. of female = 100 – 70 = 30

∴ Total unmarried person = 100–30 =70

∴ Married female = 30 – 20 = 10

Now, unmarried female = 30 – 10 = 20

∴ Required fraction = 20/30 = 2/3