Finding the Fourth Proportional to 1,057.66, 1,459.57 and 615.86

Step by Step Solution

1. Step 1: Write the proportion equation
   1,057.66 : 1,459.57 = 615.86 : x
2. Step 2: Convert to fraction form
   1,057.66/1,459.57 = 615.86/x
3. Step 3: Cross multiply
   1,057.66x = 1,459.57 × 615.86
4. Step 4: Simplify right side
   1,057.66x = 898,890.78
5. Step 5: Solve for x
   x = 898,890.78/1,057.66
6. Step 6: Final answer
   x = 849.89