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Relative
Frequency
This page provides a simple example
to illustrate the ideas behind relative frequency.
A
Biased Coin
Suppose you have a coin which you
know is biased towards Heads  this means the Heads has a greater chance of occurring.
However, you do now know what the
probability of a HEAD occurring actually is.
Suppose you tossed the coin lots of
times and go the following data
Number of tosses 
10 
20 
30 
40 
50 
Number of heads 
7 
15 
19 
28 
34 
So, to tabulate this we can extend
the table above:
Number of tosses 





60 
Number of heads 






Relative Frequency 






As you can see, the probability seems
to be around approaching a value of about 0.68 (to two decimal places).
A good estimate for
To
improve this estimate we would keep on increasing the total number of tosses.
We
can draw a graph to show how our estimates appear to be approaching 0.68
Deductions
from this and possible questions
·
P(heads)=0.68
THEREFORE P(tails)=0.32
·
If we tossed the
coin 350 times (for example) we would expect
·
If we tossed the coin 3 times –
we could find the probability of getting THREE HEADS
Head 
and 
Head 
and 
Head 
Equals 
Answer 






