Finding the Fourth Proportional to 21,260.72, 29,339.34 and 12,308.60

Step by Step Solution

1. Step 1: Write the proportion equation
   21,260.72 : 29,339.34 = 12,308.60 : x
2. Step 2: Convert to fraction form
   21,260.72/29,339.34 = 12,308.60/x
3. Step 3: Cross multiply
   21,260.72x = 29,339.34 × 12,308.60
4. Step 4: Simplify right side
   21,260.72x = 361,126,200.32
5. Step 5: Solve for x
   x = 361,126,200.32/21,260.72
6. Step 6: Final answer
   x = 16,985.61