A dart board has 10 equally sized slices numbered from 1-10. some are grey and some are white. the slices numbered 1,2,3,4,5,6,8,9 and 10 are grey. the slice number 7 is white. a dart is tossed and lands on a slice at random. let X be the event that the dart lands on a grey slice, and let P(X) be the probability of x. let not X be the event that the dart lands on a slice that is not grey, and let P( not X) be the probability of not X.