Finding the Fourth Proportional to 1,227.12, 1,839.78 and 577.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,227.12 : 1,839.78 = 577.50 : x
2. Step 2: Convert to fraction form
   1,227.12/1,839.78 = 577.50/x
3. Step 3: Cross multiply
   1,227.12x = 1,839.78 × 577.50
4. Step 4: Simplify right side
   1,227.12x = 1,062,472.95
5. Step 5: Solve for x
   x = 1,062,472.95/1,227.12
6. Step 6: Final answer
   x = 865.83