Answer:
20 Players
Explanation:
The number of players remaining decreases by half with each round played. This can be represented by a 50% decrease in the number of players per round, which means that this is an exponential decay situation.
The number of players remaining after x rounds can be represented by an exponential expression, a(b)x, where a represents the initial number of players, b represents the growth or decay factor, and x represents the number of rounds. Determine b by solving the formula, b = 1 - r, when r = 0.50.

It is given that a = 320 and x = 4. Substitute these values along with b = 0.50 into the general exponential expression.

Let y represent the number of players remaining after 4 rounds. Set this equal to the expression representing the number of players after 4 rounds and evaluate for y.

Therefore, after 4 rounds, there will be 20 players remaining in the tournament.