Respuesta :
Let us begin by defining the formula for calculating probability of an event occuring:
[tex]P(an\text{ event occuring) = }\frac{Number\text{ of times the event occured}}{Total\text{ number of trials}}[/tex]Before we proceed, let us enumerate the given variables
121 people walked by the store
52 came into the store
29 bought something
(a) The probability that a person who walked by the store would come into the store:
[tex]P\text{ = }\frac{Number\text{ who came into the store}}{Number\text{ that walked by}}[/tex]Substituting we have:
[tex]\begin{gathered} P\text{ = }\frac{52}{121} \\ \approx\text{ 0.430} \end{gathered}[/tex]Answer: 0.430
(b) The probability that a person who enters the store will buy something
[tex]P\text{ = }\frac{Number\text{ that bought something}}{Number\text{ who entered the store}}[/tex]Substituting we have:
[tex]\begin{gathered} P\text{ = }\frac{29}{52} \\ \approx\text{ 0.558} \end{gathered}[/tex]Answer: 0.558
(c) The probability that a person who walks by the store will buy something
[tex]P\text{ = }\frac{\text{Numb}er\text{ that bought something}}{Number\text{ that walked by}}[/tex]Substituting we have:
[tex]\begin{gathered} P\text{ = }\frac{29}{121} \\ \approx\text{ 0.240 } \end{gathered}[/tex]Answer: 0.240
(d) The probability that a person who comes into the store will buy nothing
To calculate this, we use the formula:
[tex]\begin{gathered} P(A)\text{ + P(A') =1} \\ \text{Where P(A') is the probability that an event would not occur} \end{gathered}[/tex]The probability that a person who comes into the store would buy something is 0.558
Hence:
[tex]\begin{gathered} P\text{ = 1 - 0.558} \\ =\text{ 0.442} \end{gathered}[/tex]Answer: 0.442