Finding the Fourth Proportional to 21,916.27, 30,238.77 and 13,415.32

Step by Step Solution

1. Step 1: Write the proportion equation
   21,916.27 : 30,238.77 = 13,415.32 : x
2. Step 2: Convert to fraction form
   21,916.27/30,238.77 = 13,415.32/x
3. Step 3: Cross multiply
   21,916.27x = 30,238.77 × 13,415.32
4. Step 4: Simplify right side
   21,916.27x = 405,662,775.96
5. Step 5: Solve for x
   x = 405,662,775.96/21,916.27
6. Step 6: Final answer
   x = 18,509.66