Question

use the frequency distribution to the right, which shows the number of voters (in millions) according to age, to find the probability that a voter chosen at random is in the given age range:
not between 18 to 20 years old
the probability is
(round to three decimal places as needed.)

Explanation:

Step1: Calculate total number of voters

Sum up all frequencies: $7.8 + 9.5+24.1 + 26.4+52.8+29.2=\sum_{i = 1}^{6}f_i=149.8$

Step2: Calculate number of voters not in 18 - 20 age range

Subtract the frequency of 18 - 20 age group from total. $149.8-7.8 = 142$

Step3: Calculate the probability

Use the formula $P=\frac{\text{Number of favorable outcomes}}{\text{Total number of outcomes}}$. So $P=\frac{142}{149.8}\approx0.948$

Answer:

$0.948$