Statistics
posted by Mandy .
In a city with no cars of mixed color, 30% of the cars on the road are brown. Forty percent are either brown or green, and 10% are white.
a.) What is the probability that a randomly selected car is green?
b.) What is the probability that a randomly selected car is not brown, green, or white?
Thanks a bunch for whoever can help!?

How many cars were there altogether?

It doesn't say how many cars in total there were. Im guessing that in total these cars added up to 100%.

a.)1/5
b.)1/4 
Is there anyway that you can show me how you got that so I can understand a little better? Thanks!

a.)40% of cars are either brown or green. Divide that by two since there are two colors. You get 20. Put that over 100=20/100. Reduce it to 2/10 which reduces to 1/5.
b.)Add all the percents together to get 80%. Subtract it from 100. 10080=20. 20/100=1/5. So the actual answer to b is 1/5. Sorry, my mistake. :P 
Thanks a bunch!

No problem.(:

What about the undefined remaining 20%?
30% + 40% + 10% = only 80% 
She DID do that.