Hi guys, below are some questions I am unsure about! Appreciate if you could clarify my doubts! Thanks!
A survey is conducted with 100 students on their favourite car brands. They tabulated the collected data as follows:
Brand Percentage
Mercedes 17.5%
Toyota 35%
BMW 13%
Mazda 28%
Others x%
(i) Comment on the validity of the numerical figures shown under the Percentage column. Correct any error that you may detect.
Unsure: The numerical figures are valid (?) as long as they add up to 100%? Not sure if there are errors there. One possible error I could thought of is the percentage must be whole number? As assuming 1% represent 1 student since there are 100 students. (Not sure if this reasoning is right) Or there are no errors?
(ii) Taking into account your answer in (i), identify the value of x if the percentages shown are interpreted as the probabilities of favourite cars when a Singaporean is randomly asked.
X = 6.5% (assuming there are no errors above)
Or do I need to round up the Mercedes % to 18%? And x will be 6%.
(iii) Identify the probability that a random favourite car response is BMW or
Mercedes.
Do I use the addition rule or special additional rules? I’m not sure if the responses are mutually exclusive or not? How do I know if it possible if one student pick 2 responses?
P(Mercedes) + P(BMW) = 30.5%
A survey is conducted with 100 students on their favourite car brands. They tabulated the collected data as follows:
Brand Percentage
Mercedes 17.5%
Toyota 35%
BMW 13%
Mazda 28%
Others x%
(i) Comment on the validity of the numerical figures shown under the Percentage column. Correct any error that you may detect.
Unsure: The numerical figures are valid (?) as long as they add up to 100%? Not sure if there are errors there. One possible error I could thought of is the percentage must be whole number? As assuming 1% represent 1 student since there are 100 students. (Not sure if this reasoning is right) Or there are no errors?
(ii) Taking into account your answer in (i), identify the value of x if the percentages shown are interpreted as the probabilities of favourite cars when a Singaporean is randomly asked.
X = 6.5% (assuming there are no errors above)
Or do I need to round up the Mercedes % to 18%? And x will be 6%.
(iii) Identify the probability that a random favourite car response is BMW or
Mercedes.
Do I use the addition rule or special additional rules? I’m not sure if the responses are mutually exclusive or not? How do I know if it possible if one student pick 2 responses?
P(Mercedes) + P(BMW) = 30.5%