https://dasl.datadescription.com/datafile/nissan/
You are going to do some research on this dataset. By converting the Miles per Gallon (MPG) to Litres per 100km (Litre). All answers are two
decimals and must include units. (Probabilities written in this format X.XX%)
A: What are the Mean and Standard Deviation of the ‘Litres’ variable? (Use R Studio – present R
code in your answer) (2)
For the following questions, assume the distribution follows a normal distribution. When
the question asks for calculation by hand, draw a normal curve, label the mean and raw
score(s) and indicate the shaded area of interest.
B: What is the probability that a car had an efficiency above 12 Litres per 100km? (By Hand and
present R code) (3)
C: What is the probability that the car either had less than 9 Litres per 100km or more than 15
Litres per 100km ? (By Hand and present R code) (5)
D: Given that you have a defined probability value (80% Probability that fuel efficiency is less
than) what is the cut off value of the Litres per 100km that represents that probability? (By Hand
and present R code) (3)
E: What is the probability that a car efficiency was between 7.5 Litres per 100km and 9.6 Litres
per 100km? (By Hand and present R code) (5)
Assignment for personal use of registered Geog226 students – they may not be copied or redistributed in any format. © 3
Question 3
The data below is from a fictitious survey on otters. We have been monitoring the number of
times an otter visits the river bank either side of a human constructed dam. The data is presented
below. Answer with 2 decimals if reporting X.XX% or 4 decimals if reporting 0.xxxx
Visits River Bank Does not Visit
River Bank
North of Dam 175 77
South of Dam 68 105
Complete A: to D: all by hand.
A: Given that an otter visited the river bank, what is the probability that they are North of the
Dam? (2)
B: Given that we are south of the Dam, what is the probability that an otter did not visit the river
bank? (2)
C: What is the probability of a randomly selected otter being North of the Dam? (1)
D: What is the probability of a randomly selected otter has not visited the River Bank? (1)
