When you toss one coin, the probability that you'll get heads is 1/2. Assuming the coin is fair, this means that:

1)if you toss 1000 coins, theres no way to predict the precise number of heads youll get, though it will probably be close to 500.

2)if you toss 100 coins, youll get 50 heads and 50 tails.

3)

if you toss two coins, youll get 1 head and 1 tail.