maths question

Question

Some animals are twice as likely to have male babies as female babies. Explain why the probability of a male baby is 2/3

Answer 1

Twice as likely means an odds ratio of 2:1 which is equivalent to the probability of 2/3.

 

Twice as likely means that there will be 2 male babies for every 1 female...so out of 3 babies, 2 will be male, i.e. probability of 2/3.

 

Please note that what I have written is an approximation of the law of large numbers about which you might want to read!