# Probability question intuitively

There are three pregnant women who are equally likely to give birth on any of the seven days of the week.

1) Find the probability of them giving birth on the same day of the week given that they all gave birth on the weekend?

My thinking: Our sample space is now restricted to only two days of the week. Therefore, the probability of them giving birth on the same day is (0.5)^3. The answer of the book is 1/4. Is my thinking correct or am I missing something?

• Weekend means saturday and sunday. – Rishi Sep 25 '19 at 15:59

The probability that they all give birth in saturday is $$0.5^3$$. The probability that they al give birth on Sunday is $$0.5^3$$, then, the probability that they all give birth on the same day, given that they gave birth during the weekend, is $$2\times 0.5^3 =0.25$$.