Finding the Fourth Proportional to 139,479.24, 209,207 and 55,216.50

Step by Step Solution

1. Step 1: Write the proportion equation
   139,479.24 : 209,207 = 55,216.50 : x
2. Step 2: Convert to fraction form
   139,479.24/209,207 = 55,216.50/x
3. Step 3: Cross multiply
   139,479.24x = 209,207 × 55,216.50
4. Step 4: Simplify right side
   139,479.24x = 11,551,678,315.50
5. Step 5: Solve for x
   x = 11,551,678,315.50/139,479.24
6. Step 6: Final answer
   x = 82,820.05