How do you solve if you throw a 6 sided die 84 times how many time would you expect 4 to come up?

If it is a fair die, the probability of throwing a 4 in a single go is 1/6. That is, you expect to get a 4 in 1/6 of the throws. So for 84 throws you would expect to get a 4 in 84*(1/6) = 14 times.