Finding the Fourth Proportional to 2,545.20, 3,818.90 and 986.31

Step by Step Solution

1. Step 1: Write the proportion equation
   2,545.20 : 3,818.90 = 986.31 : x
2. Step 2: Convert to fraction form
   2,545.20/3,818.90 = 986.31/x
3. Step 3: Cross multiply
   2,545.20x = 3,818.90 × 986.31
4. Step 4: Simplify right side
   2,545.20x = 3,766,621.72
5. Step 5: Solve for x
   x = 3,766,621.72/2,545.20
6. Step 6: Final answer
   x = 1,479.89