Qno14-Graded assignment Week 3

[Deepthi Menon]

Hello academic team,

I am not convinced with the answer for Q no 14. If there are 18 people in the group,

n=18 and p=70; then np = 12.6. By that rule, the 13th person is 70p.

Hence we have only 5 people taller than the 13th person.

5/18 ~ 27& which is less than 30%. Hence the option which you have identified as correct option is wrong [ 30% of people are taller than you]

However, if we take 13/18, we get 72.2% which is higher than 70%. Thus the only option that is correct is 

70% of people are shorter than or same height as you.  

Can you please clarify? Please don't respond with the usual - refer the solution to graded assignment. Please respond to my specific doubt.

Thanks

Deepthi

[Statistics 1 Support 1]

Hello,

Since the data contains 18 people, the 70th percentile value is approximated to 13th person value. It means that 5 persons have a height greater than or equal to 70th percentile value.  For this question, we are awarding marks to everyone since the statement of "30% are taller than you" is not correct. Your statement of ~27% is not entirely correct. Even the observation after 13th person could have the same value as the 13th person. So, when the person is 70th percentile it means that 30% are taller or equal to his height. And 70% of people are shorter or equal to his height.

Thanks & Regards,
Ram,
Course Support Team