Finding the Fourth Proportional to 11,978.72, 16,514.52 and 8,388.86

Step by Step Solution

1. Step 1: Write the proportion equation
   11,978.72 : 16,514.52 = 8,388.86 : x
2. Step 2: Convert to fraction form
   11,978.72/16,514.52 = 8,388.86/x
3. Step 3: Cross multiply
   11,978.72x = 16,514.52 × 8,388.86
4. Step 4: Simplify right side
   11,978.72x = 138,537,913.67
5. Step 5: Solve for x
   x = 138,537,913.67/11,978.72
6. Step 6: Final answer
   x = 11,565.34