Finding the Fourth Proportional to 139,836.78, 209,568.33 and 51,006.78

Step by Step Solution

1. Step 1: Write the proportion equation
   139,836.78 : 209,568.33 = 51,006.78 : x
2. Step 2: Convert to fraction form
   139,836.78/209,568.33 = 51,006.78/x
3. Step 3: Cross multiply
   139,836.78x = 209,568.33 × 51,006.78
4. Step 4: Simplify right side
   139,836.78x = 10,689,405,703.28
5. Step 5: Solve for x
   x = 10,689,405,703.28/139,836.78
6. Step 6: Final answer
   x = 76,442.02