Proababilty

A family has j children with probability pj, where p1=.1, p2=.25, p3=.35, p4=.3. A child is randomly chosen. Given that this child is eldest in the family, find the conditional probability that the family has (a) only one child (b) 4 children. How would the answer differ if the randomly selected child is the youngest in the family?

#Probability #ProbabilityTree

Easy Math Editor

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Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$