Finding the Fourth Proportional to 12,185.34, 16,819.85 and 8,642.40

Step by Step Solution

1. Step 1: Write the proportion equation
   12,185.34 : 16,819.85 = 8,642.40 : x
2. Step 2: Convert to fraction form
   12,185.34/16,819.85 = 8,642.40/x
3. Step 3: Cross multiply
   12,185.34x = 16,819.85 × 8,642.40
4. Step 4: Simplify right side
   12,185.34x = 145,363,830.17
5. Step 5: Solve for x
   x = 145,363,830.17/12,185.34
6. Step 6: Final answer
   x = 11,929.41