Finding the Fourth Proportional to 139,620.42, 192,589.78 and 121,758.30

Step by Step Solution

1. Step 1: Write the proportion equation
   139,620.42 : 192,589.78 = 121,758.30 : x
2. Step 2: Convert to fraction form
   139,620.42/192,589.78 = 121,758.30/x
3. Step 3: Cross multiply
   139,620.42x = 192,589.78 × 121,758.30
4. Step 4: Simplify right side
   139,620.42x = 23,449,404,210.17
5. Step 5: Solve for x
   x = 23,449,404,210.17/139,620.42
6. Step 6: Final answer
   x = 167,951.11