3 variables, level of significance...help!

I'm having trouble with this problem. It's different from anything I've come across so far and I'm not sure how to begin. Here it is:

John, Ken, and Mike all think they spend more time watching TV than the other 2. For each of 10 days, they record the number of hours each watches TV. For the 10 days, John watched an average of 7 hours per day with a standard deviation of 1 hour. Ken watched an average of 8 hours with a standard deviation of 1.5hours. Mike watched an average of 10 hours with a standard deviation of 2 hours. Is there statistical evidence to suggest that the mean number of hours that John, Ken, and Mike watch TV per day are not equal at a .05 level of significance?

Thanks for any help!