SOLUTION: Please help me figure out how to solve this word problem: "Our city has 2400 subscribers for HipHop magazines Of these, 1200 subscribe to Magazine A, 500 subscribe to Magazine B, a

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: Please help me figure out how to solve this word problem: "Our city has 2400 subscribers for HipHop magazines Of these, 1200 subscribe to Magazine A, 500 subscribe to Magazine B, a      Log On


   



Question 6585: Please help me figure out how to solve this word problem: "Our city has 2400 subscribers for HipHop magazines Of these, 1200 subscribe to Magazine A, 500 subscribe to Magazine B, and 100 subscribe to both. What is the probability that a subscriber selected at random subscribes to either Magazine A or B?"
I have definitely attempted trying to solve this problem, but I end up confusing myself after I try and double-check my answer, because on a couple of tries, I got different answers.
Thanks,
cloecloud

Answer by Mike(39) About Me  (Show Source):
You can put this solution on YOUR website!
Best thing to do with these questions is to draw a Venn diagram, which makes it easier to visualize the problem. I can't do that for you via the internet, but I'm sure you know what I mean because you're doing probability and Venn diagrams are a central part of probability. Basically you draw two circles that partially intersect each other within a rectangle. One of the circles is called Magazine A, and other Magazine B. Then you simply fill in the information you're given. Written mathetmatically, what they're asking you to find is P(AuB), which stands for the probability of AorB. The formula for this is P(AuB)=P(A)+P(B)-P(AnB). All you do now is plug in the values. Therefore:
P(AuB)=1200/2400+500/2400-100/2400=.5+5/24-1/24= 2/3 which is your answer.
Hope that helps.
Regards,
-Mike