Finding the Fourth Proportional to 21,238.91, 29,309.82 and 11,679.42

Step by Step Solution

1. Step 1: Write the proportion equation
   21,238.91 : 29,309.82 = 11,679.42 : x
2. Step 2: Convert to fraction form
   21,238.91/29,309.82 = 11,679.42/x
3. Step 3: Cross multiply
   21,238.91x = 29,309.82 × 11,679.42
4. Step 4: Simplify right side
   21,238.91x = 342,321,599.15
5. Step 5: Solve for x
   x = 342,321,599.15/21,238.91
6. Step 6: Final answer
   x = 16,117.66