Finding the Fourth Proportional to 139,668.88, 207,923.86 and 138,838.72

Step by Step Solution

1. Step 1: Write the proportion equation
   139,668.88 : 207,923.86 = 138,838.72 : x
2. Step 2: Convert to fraction form
   139,668.88/207,923.86 = 138,838.72/x
3. Step 3: Cross multiply
   139,668.88x = 207,923.86 × 138,838.72
4. Step 4: Simplify right side
   139,668.88x = 28,867,882,579.86
5. Step 5: Solve for x
   x = 28,867,882,579.86/139,668.88
6. Step 6: Final answer
   x = 206,688.01