Finding the Fourth Proportional to 12,085.86, 18,107.58 and 8,390.46

Step by Step Solution

1. Step 1: Write the proportion equation
   12,085.86 : 18,107.58 = 8,390.46 : x
2. Step 2: Convert to fraction form
   12,085.86/18,107.58 = 8,390.46/x
3. Step 3: Cross multiply
   12,085.86x = 18,107.58 × 8,390.46
4. Step 4: Simplify right side
   12,085.86x = 151,930,925.69
5. Step 5: Solve for x
   x = 151,930,925.69/12,085.86
6. Step 6: Final answer
   x = 12,570.97