Finding the Fourth Proportional to 209,131.57, 288,603.40 and 113,638.27

Step by Step Solution

1. Step 1: Write the proportion equation
   209,131.57 : 288,603.40 = 113,638.27 : x
2. Step 2: Convert to fraction form
   209,131.57/288,603.40 = 113,638.27/x
3. Step 3: Cross multiply
   209,131.57x = 288,603.40 × 113,638.27
4. Step 4: Simplify right side
   209,131.57x = 32,796,391,092.12
5. Step 5: Solve for x
   x = 32,796,391,092.12/209,131.57
6. Step 6: Final answer
   x = 156,821.81