Finding the Fourth Proportional to 12,109.78, 16,700.40 and 7,856.44

Step by Step Solution

1. Step 1: Write the proportion equation
   12,109.78 : 16,700.40 = 7,856.44 : x
2. Step 2: Convert to fraction form
   12,109.78/16,700.40 = 7,856.44/x
3. Step 3: Cross multiply
   12,109.78x = 16,700.40 × 7,856.44
4. Step 4: Simplify right side
   12,109.78x = 131,205,690.58
5. Step 5: Solve for x
   x = 131,205,690.58/12,109.78
6. Step 6: Final answer
   x = 10,834.69