Finding the Fourth Proportional to 21,111.57, 29,133.96 and 11,680.14

Step by Step Solution

1. Step 1: Write the proportion equation
   21,111.57 : 29,133.96 = 11,680.14 : x
2. Step 2: Convert to fraction form
   21,111.57/29,133.96 = 11,680.14/x
3. Step 3: Cross multiply
   21,111.57x = 29,133.96 × 11,680.14
4. Step 4: Simplify right side
   21,111.57x = 340,288,731.55
5. Step 5: Solve for x
   x = 340,288,731.55/21,111.57
6. Step 6: Final answer
   x = 16,118.59