Finding the Fourth Proportional to 139,005.90, 208,476.78 and 82,861.80

Step by Step Solution

1. Step 1: Write the proportion equation
   139,005.90 : 208,476.78 = 82,861.80 : x
2. Step 2: Convert to fraction form
   139,005.90/208,476.78 = 82,861.80/x
3. Step 3: Cross multiply
   139,005.90x = 208,476.78 × 82,861.80
4. Step 4: Simplify right side
   139,005.90x = 17,274,761,249.00
5. Step 5: Solve for x
   x = 17,274,761,249.00/139,005.90
6. Step 6: Final answer
   x = 124,273.58