Finding the Fourth Proportional to 139,098.78, 191,965.86 and 78,669.45

Step by Step Solution

1. Step 1: Write the proportion equation
   139,098.78 : 191,965.86 = 78,669.45 : x
2. Step 2: Convert to fraction form
   139,098.78/191,965.86 = 78,669.45/x
3. Step 3: Cross multiply
   139,098.78x = 191,965.86 × 78,669.45
4. Step 4: Simplify right side
   139,098.78x = 15,101,848,624.98
5. Step 5: Solve for x
   x = 15,101,848,624.98/139,098.78
6. Step 6: Final answer
   x = 108,569.24