Finding the Fourth Proportional to 139,403.76, 208,978.92 and 50,619.12

Step by Step Solution

1. Step 1: Write the proportion equation
   139,403.76 : 208,978.92 = 50,619.12 : x
2. Step 2: Convert to fraction form
   139,403.76/208,978.92 = 50,619.12/x
3. Step 3: Cross multiply
   139,403.76x = 208,978.92 × 50,619.12
4. Step 4: Simplify right side
   139,403.76x = 10,578,329,028.95
5. Step 5: Solve for x
   x = 10,578,329,028.95/139,403.76
6. Step 6: Final answer
   x = 75,882.67