Finding the Fourth Proportional to 21,086.64, 29,100.15 and 11,655.81

Step by Step Solution

1. Step 1: Write the proportion equation
   21,086.64 : 29,100.15 = 11,655.81 : x
2. Step 2: Convert to fraction form
   21,086.64/29,100.15 = 11,655.81/x
3. Step 3: Cross multiply
   21,086.64x = 29,100.15 × 11,655.81
4. Step 4: Simplify right side
   21,086.64x = 339,185,819.37
5. Step 5: Solve for x
   x = 339,185,819.37/21,086.64
6. Step 6: Final answer
   x = 16,085.34