Finding the Fourth Proportional to 139,373.98, 192,341.38 and 78,121.28

Step by Step Solution

1. Step 1: Write the proportion equation
   139,373.98 : 192,341.38 = 78,121.28 : x
2. Step 2: Convert to fraction form
   139,373.98/192,341.38 = 78,121.28/x
3. Step 3: Cross multiply
   139,373.98x = 192,341.38 × 78,121.28
4. Step 4: Simplify right side
   139,373.98x = 15,025,954,802.57
5. Step 5: Solve for x
   x = 15,025,954,802.57/139,373.98
6. Step 6: Final answer
   x = 107,810.33