Finding the Fourth Proportional to 1,057.61, 1,459.47 and 615.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,057.61 : 1,459.47 = 615.50 : x
2. Step 2: Convert to fraction form
   1,057.61/1,459.47 = 615.50/x
3. Step 3: Cross multiply
   1,057.61x = 1,459.47 × 615.50
4. Step 4: Simplify right side
   1,057.61x = 898,300.81
5. Step 5: Solve for x
   x = 898,300.81/1,057.61
6. Step 6: Final answer
   x = 849.37