1. ## Probability Models

Hello all, I missed a few days in my statistics class, and I need help with some homework, the question is as follows:

Information:

According to the current population survey, the following table summarizes probabilities for randomly selecting a full-time student in various age groups:

Age 15-17 18-24 25-34 35 or older
Probability 0.007 0.573 0.260 0.160

Question: If we randomly select a full time student, what is the probability that he/she is 25 or older?

Second question: If we randomly select a full time student, what is the probability that he/she is NOT 18-24 years old?

I would appreciate solutions, and/or the steps that must be taken to find them.

regards,
-andrew

2. ## Re: Probability Models

Originally Posted by arrogantandy
Hello all, I missed a few days in my statistics class, and I need help with some homework, the question is as follows:
Information: According to the current population survey, the following table summarizes probabilities for randomly selecting a full-time student in various age groups:
Age 15-17 18-24 25-34 35 or older
Probability 0.007 0.573 0.260 0.160

Question: If we randomly select a full time student, what is the probability that he/she is 25 or older?
Second question: If we randomly select a full time student, what is the probability that he/she is NOT 18-24 years old?
I would appreciate solutions, and/or the steps that must be taken to find them.
This is not a tutorial service. Therefore, do not ask for a step-by-step solution. You can pay a tutor for that. We are free.

Now you need to show some effort,

For a) there are two numbers to add for at least 25. What is the sum?