Finding the Fourth Proportional to 139,133.69, 208,708.82 and 53,745.20

Step by Step Solution

1. Step 1: Write the proportion equation
   139,133.69 : 208,708.82 = 53,745.20 : x
2. Step 2: Convert to fraction form
   139,133.69/208,708.82 = 53,745.20/x
3. Step 3: Cross multiply
   139,133.69x = 208,708.82 × 53,745.20
4. Step 4: Simplify right side
   139,133.69x = 11,217,095,960.39
5. Step 5: Solve for x
   x = 11,217,095,960.39/139,133.69
6. Step 6: Final answer
   x = 80,620.99