Question

john and lauren are looking for a good neighborhood to raise their children. they want neighbors who have kids and who are fellow rollerbladers as well. the couple surveys a random sample of residents in a nice - looking neighborhood. their results are shown below. david, anastasia, and miles live in the neighborhood. david is focusing on his career and does not have children. anastasia has never rollerbladed. all we know about miles is that he is very tall. calculate the following probabilities based on the frequency table below. round to the nearest hundredth of a percent.
rollerblader not a rollerblader
kids 41 3 column total 44
no kids 9 9 18
row total 50 12 62
probability that david is a rollerblader =
probability that anastasia does not have kids =
probability that miles is a rollerblader =

Explanation:

Step1: Definir la fórmula de probabilidad

La probabilidad $P(A)=\frac{\text{número de casos favorables}}{\text{número total de casos}}$

Step2: Probabilidad de que Miles sea un patinador

El número de casos favorables (Miles es patinador) es $44$ y el número total de casos es $62$. Entonces $P(\text{Miles es patinador})=\frac{44}{62}\approx 0.7097$. Convertido a porcentaje: $0.7097\times100 = 70.97\%\approx71\%$

Step3: Probabilidad de que Anastasia no tenga hijos

El número de casos favorables (Anastasia no tiene hijos) es $9$ y el número total de casos (Anastasia) es $18$. Entonces $P(\text{Anastasia no tiene hijos})=\frac{9}{18}=0.5$. Convertido a porcentaje: $0.5\times 100 = 50\%$

Step4: Probabilidad de que David sea un patinador

El número de casos favorables (David es patinador) es $3$ y el número total de casos (David) es $12$. Entonces $P(\text{David es patinador})=\frac{3}{12}=0.25$. Convertido a porcentaje: $0.25\times 100 = 25\%$

Answer:

Probabilidad que Miles es un patinador = $71\%$
Probabilidad que Anastasia no tiene hijos = $50\%$
Probabilidad que David es un patinador = $25\%$