Final answer:
Dave weighed 200 pounds before.
Step-by-step explanation:
To find out how much Dave weighed before, we need to calculate his weight before gaining the 24.3%. Let's represent Dave's weight before as 'x'. We know that the weight after gaining 24.3% is 230 pounds. So, we can set up the equation: x + 0.243x = 230. Solving this equation, we find that x = 200 pounds. Therefore, Dave weighed 200 pounds before.