Time Mag and Sports Illustrated Probability

[Navyguy]

Of 200 students surveyed 40 subscribe to Time Magazine, 65 subscribe to Sports Illustrated, and 10 subscribe to both. If a student is selected at random, what is the probability the student subscribes to Time Magazine or Sorts Illustrated?

Ok I look at it this way:

200 students TM 40
SPL 65
BOTH 10
total 115 Using the Inclusion - Exclusion Principle, My answer is 95/200, is this right if not please show me how to set this one up. Thanks for taking time and looking over this problem.

 

[galactus]

T=Time
SI=Sports Illustrated
B=Both=T and SI


\(\displaystyle \L\\P(T)+P(SI)-P(T\;\ and\;\ SI)=P(T\;\ or\;\ SI)\)

\(\displaystyle \L\\\frac{40}{200}+\frac{65}{200}-\frac{10}{200}=\frac{1}{5}+\frac{13}{40}-\frac{1}{20}=\frac{19}{40}\)

That's the same as 95/200, only reduced. Good job.

 

[Navyguy]

thanks

I like the way you did it also, thanks soooooo much for checking and helping me out.