Finding the Fourth Proportional to 12,386.10, 18,615.60 and 10,782.30

Step by Step Solution

1. Step 1: Write the proportion equation
   12,386.10 : 18,615.60 = 10,782.30 : x
2. Step 2: Convert to fraction form
   12,386.10/18,615.60 = 10,782.30/x
3. Step 3: Cross multiply
   12,386.10x = 18,615.60 × 10,782.30
4. Step 4: Simplify right side
   12,386.10x = 200,718,983.88
5. Step 5: Solve for x
   x = 200,718,983.88/12,386.10
6. Step 6: Final answer
   x = 16,205.18