Finding the Fourth Proportional to 11,978.48, 17,862.20 and 11,147.42

Step by Step Solution

1. Step 1: Write the proportion equation
   11,978.48 : 17,862.20 = 11,147.42 : x
2. Step 2: Convert to fraction form
   11,978.48/17,862.20 = 11,147.42/x
3. Step 3: Cross multiply
   11,978.48x = 17,862.20 × 11,147.42
4. Step 4: Simplify right side
   11,978.48x = 199,117,445.52
5. Step 5: Solve for x
   x = 199,117,445.52/11,978.48
6. Step 6: Final answer
   x = 16,622.93