Finding the Fourth Proportional to 2,185.81, 3,278.71 and 724.57

Step by Step Solution

1. Step 1: Write the proportion equation
   2,185.81 : 3,278.71 = 724.57 : x
2. Step 2: Convert to fraction form
   2,185.81/3,278.71 = 724.57/x
3. Step 3: Cross multiply
   2,185.81x = 3,278.71 × 724.57
4. Step 4: Simplify right side
   2,185.81x = 2,375,654.90
5. Step 5: Solve for x
   x = 2,375,654.90/2,185.81
6. Step 6: Final answer
   x = 1,086.85