Final answer:
To find the number of boards in the stack, divide the stack height by the thickness of each board. In this case, there are 32 boards in the stack.
Step-by-step explanation:
To find the number of boards in the stack, we need to determine the total thickness of the stack and then divide it by the thickness of each board. The stack is 24 inches high, and each board is 3/4 inch thick. Therefore, the total thickness of the stack is 24 / (3/4) = 24 * (4/3) = 96/3 = 32 boards.