Finding the Fourth Proportional to 11,665.16, 17,478.26 and 8,196.20

Step by Step Solution

1. Step 1: Write the proportion equation
   11,665.16 : 17,478.26 = 8,196.20 : x
2. Step 2: Convert to fraction form
   11,665.16/17,478.26 = 8,196.20/x
3. Step 3: Cross multiply
   11,665.16x = 17,478.26 × 8,196.20
4. Step 4: Simplify right side
   11,665.16x = 143,255,314.61
5. Step 5: Solve for x
   x = 143,255,314.61/11,665.16
6. Step 6: Final answer
   x = 12,280.61