Finding the Fourth Proportional to 21,387.72, 29,501.15 and 13,718.86

Step by Step Solution

1. Step 1: Write the proportion equation
   21,387.72 : 29,501.15 = 13,718.86 : x
2. Step 2: Convert to fraction form
   21,387.72/29,501.15 = 13,718.86/x
3. Step 3: Cross multiply
   21,387.72x = 29,501.15 × 13,718.86
4. Step 4: Simplify right side
   21,387.72x = 404,722,081.51
5. Step 5: Solve for x
   x = 404,722,081.51/21,387.72
6. Step 6: Final answer
   x = 18,923.11