We are given a table of frequencies, so in order to find probability associated with it, we need to start by adding all the numbers in the frequency, since that would give us the totals:
We add :
7.7 + 8.2 + 24.1 + 25.6 + 51.5 + 29. 4 = 146.5
Now, notice that they ask you to find the probability associated with a voter chosen at random to be in a group DIFFERENT from the range 21 to 24, That means the complementary of this range, which is therefore
146.5 - 8.2 = 138.3 (since 8.2 is the frequency for the 21 - 24 years/age range.
Then the probability is the quotient:
138.3 / 146.5 = 0.9440273 which in percent terms is 94.4 %
If you teacher wants the probaility in decimal (math) form, use 0.944.
If he/she wants it in percent form, use 94.403% (using
