Finding the Fourth Proportional to 139,767.30, 209,564.55 and 80,573.70

Step by Step Solution

1. Step 1: Write the proportion equation
   139,767.30 : 209,564.55 = 80,573.70 : x
2. Step 2: Convert to fraction form
   139,767.30/209,564.55 = 80,573.70/x
3. Step 3: Cross multiply
   139,767.30x = 209,564.55 × 80,573.70
4. Step 4: Simplify right side
   139,767.30x = 16,885,391,182.34
5. Step 5: Solve for x
   x = 16,885,391,182.34/139,767.30
6. Step 6: Final answer
   x = 120,810.74