Finding the Fourth Proportional to 139,838.78, 209,571.32 and 51,008.78

Step by Step Solution

1. Step 1: Write the proportion equation
   139,838.78 : 209,571.32 = 51,008.78 : x
2. Step 2: Convert to fraction form
   139,838.78/209,571.32 = 51,008.78/x
3. Step 3: Cross multiply
   139,838.78x = 209,571.32 × 51,008.78
4. Step 4: Simplify right side
   139,838.78x = 10,689,977,356.19
5. Step 5: Solve for x
   x = 10,689,977,356.19/139,838.78
6. Step 6: Final answer
   x = 76,445.01