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# Stats Q. HELP! watch

1. The times for a certain car journey have a normal distribution with mean 100 minutes and standard deviation 7 minutes. Journey times are classiﬁed as follows:
‘short’ (the shortest 33% of times),
‘long’ (the longest 33% of times),
‘standard’ (the remaining 34% of times).
(i) Find the probability that a randomly chosen car journey takes between 85 and 100 minutes.
(ii) Find the least and greatest times for ‘standard’ journeys.

Sol. (i) I got 0.484 as answer by solving P(85<X<100).
I am really confused on (ii).
The times for a certain car journey have a normal distribution with mean 100 minutes and standard deviation 7 minutes. Journey times are classiﬁed as follows:
‘short’ (the shortest 33% of times),
‘long’ (the longest 33% of times),
‘standard’ (the remaining 34% of times).
(i) Find the probability that a randomly chosen car journey takes between 85 and 100 minutes.
(ii) Find the least and greatest times for ‘standard’ journeys.

Sol. (i) I got 0.484 as answer by solving P(85<X<100).
I am really confused on (ii).
If we consider 'short' times. These are the shortest 33% of times so if is the greatest short time then it must be true that

. Does this make sense? And can you use this hint to answer the question?

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