Finding the Fourth Proportional to 21,309.67, 29,413.80 and 12,359.37

Step by Step Solution

1. Step 1: Write the proportion equation
   21,309.67 : 29,413.80 = 12,359.37 : x
2. Step 2: Convert to fraction form
   21,309.67/29,413.80 = 12,359.37/x
3. Step 3: Cross multiply
   21,309.67x = 29,413.80 × 12,359.37
4. Step 4: Simplify right side
   21,309.67x = 363,536,037.31
5. Step 5: Solve for x
   x = 363,536,037.31/21,309.67
6. Step 6: Final answer
   x = 17,059.67