Finding the Fourth Proportional to 139,892.40, 209,887.20 and 61,063.20

Step by Step Solution

1. Step 1: Write the proportion equation
   139,892.40 : 209,887.20 = 61,063.20 : x
2. Step 2: Convert to fraction form
   139,892.40/209,887.20 = 61,063.20/x
3. Step 3: Cross multiply
   139,892.40x = 209,887.20 × 61,063.20
4. Step 4: Simplify right side
   139,892.40x = 12,816,384,071.04
5. Step 5: Solve for x
   x = 12,816,384,071.04/139,892.40
6. Step 6: Final answer
   x = 91,616.01