The probability of a boy or a girl being born is 1/2. For a family having only three children, what is the probability of having two girls and one boy?
There are $2^3 = 8$ equally likely sequences of three births. The ones with two girls and one boy are GGB, GBG and BGG, 3 in all, so the probability is $\frac{3}{8}$ (or $\binom{3}{2}\left(\frac{1}{2}\right)^3$).
More Quantitative Aptitude: Data Interpretation, Arithmetic and Number Computation questions
GATE 2024 PI Q8– Person 1 and Person 2 invest in three mutual funds A, B, and C. The amounts they invest in…
GATE 2023 PI Q7– To construct a wall, sand and cement are mixed in the ratio of 3:1. The cost of sand and…
GATE 2022 PI Q3– P and Q fill a tank in 10 and 6 minutes respectively. R drains 34 litres/min. All operate…
GATE 2022 PI Q7– Each shown disk has eight equally likely outcomes 1–8. Two arrows are spun independently.…
GATE 2021 PI Q1– A city currently has population 1102500, increasing at 5% per annum. What was its…
GATE 2021 PI Q9– The bar chart shows minutes X and Y exercise each day of a week. On how many days does one…