Finding the Fourth Proportional to 138,866, 208,308.72 and 55,760

Step by Step Solution

1. Step 1: Write the proportion equation
   138,866 : 208,308.72 = 55,760 : x
2. Step 2: Convert to fraction form
   138,866/208,308.72 = 55,760/x
3. Step 3: Cross multiply
   138,866x = 208,308.72 × 55,760
4. Step 4: Simplify right side
   138,866x = 11,615,294,227.20
5. Step 5: Solve for x
   x = 11,615,294,227.20/138,866
6. Step 6: Final answer
   x = 83,643.90