Finding the Fourth Proportional to 1,087.50, 1,500.78 and 615.58

Step by Step Solution

1. Step 1: Write the proportion equation
   1,087.50 : 1,500.78 = 615.58 : x
2. Step 2: Convert to fraction form
   1,087.50/1,500.78 = 615.58/x
3. Step 3: Cross multiply
   1,087.50x = 1,500.78 × 615.58
4. Step 4: Simplify right side
   1,087.50x = 923,850.15
5. Step 5: Solve for x
   x = 923,850.15/1,087.50
6. Step 6: Final answer
   x = 849.52