Question

In a national survey college students were​ asked, "How often do you wear a seat belt when riding in a car driven by someone​ else?" The response frequencies appear in the table to the right.​ (a) Construct a probability model for​ seat-belt use by a passenger.​ (b) Would you consider it unusual to find a college student who never wears a seat belt when riding in a car driven by someone​ else?

Response   Frequency
Never   125
Rarely   305
Sometimes   530
Most of the time   1318
Always   2285

Answer 1

a)

dividing each value with total frequency:

response	frequency
never	0.0274
rarely	0.0668
sometimes	0.1162
most of the time	0.2888
always	0.5008

(please try below table if required 3 decimal places):

response	frequency
never	0.027
rarely	0.067
sometimes	0.116
most of the time	0.289
always	0.501

b)

since probabiltiy of  never wears a seat belt when riding in a car is less than 0.05 , this is considered to be unusual,