Finding the Fourth Proportional to 21,005.86, 28,987.82 and 11,446.15

Step by Step Solution

1. Step 1: Write the proportion equation
   21,005.86 : 28,987.82 = 11,446.15 : x
2. Step 2: Convert to fraction form
   21,005.86/28,987.82 = 11,446.15/x
3. Step 3: Cross multiply
   21,005.86x = 28,987.82 × 11,446.15
4. Step 4: Simplify right side
   21,005.86x = 331,798,935.89
5. Step 5: Solve for x
   x = 331,798,935.89/21,005.86
6. Step 6: Final answer
   x = 15,795.54