The variable is "Age of a student"
The table shows you the values that this variable can take and the point probability of each value.
You have to calculate the probability of a student chosen at random will be 16 or older, you can symbolize this sentence as:
[tex]P(X\ge16)[/tex]
This means that the student can be 16 or 17 or 18, you can calculate it as the union of the three events:
[tex]P(X\ge16)=P(16)+P(17)+P(18)=0.25+0.15+0.01=0.41[/tex]
The probability of a student choosen at randon being 16 years old or older is 0.41.
