Question

A family has five girls and no son. Probability of son as the 6th child will be:

• A. 50%
• B. 75%
• C. Full
• D. No chance

Answer 1

The correct option is A 50%

• Father is the person who determines the sex of the children.
• There are two types of gametes produced by father - with X chromosome and Y chromosome.
• Mother contains only X chromosome.
• If male gemete with X chromosome fuses with X chromosome of mother, it results in a female child.
• If gamete with Y chromosome fuses with X chromosome of mother, it gives a male child.
• Thus, there is 50% chance for female child and the same for male child, irrespective of the sex of the five previous children.
• Hence, correct answer is option A.