Question

 Understandable Statistics 12th edition

a) Number of traffic fatalities per year in the state of Florida

b)Distance a golf ball travels after being hit with a driver.

c) Time required to drive from home to college on any given day.

d) Number of ships in Pearl Harbor on any given day.

e) Your weight before breakfast each morning.

 

Answer 1

First let us learn the difference between discrete and continuous variables.

Discrete variables are obtained usually by counting and can take finite number of values only usually integers. For example the number that turns up when throwing a fair die is any of 1,2,3,4,5 and 6 since there are 6 faces to a die.

Continuous variables are obtained usually by measuring and can take any value between 2 points or even range upto infinity. For example the height of a person is obtained by measuring and can range normally from 50 cm to 250 cm for an adult. It can be a decimal value like 183.45 cm and not necessarily integers.

Let us go through the options

b) Distance a gold ball travels after being hit with a driver. This is a continuous variable since it can take any value in the allowable range and not just finite values like 1,2,3,4..etc. It can be 30.46 metres for example.

c)Time required to drive from home to college:

Again continuous variable since obtained by measurement via a device and not just take finite values but values withing a range. It can be 15 minutes and 13.5 seconds.

d) Number of ships in pearl harbour in any given day. Note the wording "any given day" this is important because on any given day it is obtained by counting the ships which takes positive integers or be 0 only. If it were the average for a day calculated from a years recordings then it could have been continuous because then it would take decimal values since being an average.

e) Your weight before breakfast everyday:

This is taken via measuring and is a continuous variable taking decimal values. For example 72.4 kg.

a) Number of traffic fatalities per year in Florida:

This is a bit tricky so I saved it for last, Note the wording "per year" and not "this year" or "specidfic year". Per year means that is the average values taken for pey year from a data containing many years. Whenever averaging is involved it is a continuous variable since it can take decimal values. It can be something like 1025.5 fatalities.

In other case if it were "for the year 2015" then it would be a discrete variable since it is an integer.