To calculate the fractional probability of having 1 boy and 2 girls in a family's first 3 births, we need to consider all the possible outcomes.
There are 3 possible ways to have 1 boy and 2 girls in a family's first 3 births:
1. BGG
2. GBG
3. GGB
Each birth is an independent event, so we can calculate the probability of each of these outcomes separately.
The probability of having a boy followed by 2 girls is:
(1/2) * (1/2) * (1/2) = 1/8
Since there are 3 ways to have 1 boy and 2 girls, we multiply the probability of each outcome by 3.
Fractional probability = 3 * (1/8) = 3/8
Therefore, the fractional probability of having 1 boy and 2 girls in any order in a family's first 3 births is 3/8.