Finding the Fourth Proportional to 139,007.90, 208,479.78 and 82,863.80

Step by Step Solution

1. Step 1: Write the proportion equation
   139,007.90 : 208,479.78 = 82,863.80 : x
2. Step 2: Convert to fraction form
   139,007.90/208,479.78 = 82,863.80/x
3. Step 3: Cross multiply
   139,007.90x = 208,479.78 × 82,863.80
4. Step 4: Simplify right side
   139,007.90x = 17,275,426,793.96
5. Step 5: Solve for x
   x = 17,275,426,793.96/139,007.90
6. Step 6: Final answer
   x = 124,276.58