Finding the Fourth Proportional to 2,459.31, 3,689.01 and 815.87

Step by Step Solution

1. Step 1: Write the proportion equation
   2,459.31 : 3,689.01 = 815.87 : x
2. Step 2: Convert to fraction form
   2,459.31/3,689.01 = 815.87/x
3. Step 3: Cross multiply
   2,459.31x = 3,689.01 × 815.87
4. Step 4: Simplify right side
   2,459.31x = 3,009,734.14
5. Step 5: Solve for x
   x = 3,009,734.14/2,459.31
6. Step 6: Final answer
   x = 1,223.81