Finding the Fourth Proportional to 21,004.72, 28,987.17 and 12,053.86

Step by Step Solution

1. Step 1: Write the proportion equation
   21,004.72 : 28,987.17 = 12,053.86 : x
2. Step 2: Convert to fraction form
   21,004.72/28,987.17 = 12,053.86/x
3. Step 3: Cross multiply
   21,004.72x = 28,987.17 × 12,053.86
4. Step 4: Simplify right side
   21,004.72x = 349,407,288.98
5. Step 5: Solve for x
   x = 349,407,288.98/21,004.72
6. Step 6: Final answer
   x = 16,634.70