Finding the Fourth Proportional to 2,185.62, 3,278.56 and 724.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,185.62 : 3,278.56 = 724.78 : x
2. Step 2: Convert to fraction form
   2,185.62/3,278.56 = 724.78/x
3. Step 3: Cross multiply
   2,185.62x = 3,278.56 × 724.78
4. Step 4: Simplify right side
   2,185.62x = 2,376,234.72
5. Step 5: Solve for x
   x = 2,376,234.72/2,185.62
6. Step 6: Final answer
   x = 1,087.21