Finding the Fourth Proportional to 12,940.32, 17,856.18 and 8,690.52

Step by Step Solution

1. Step 1: Write the proportion equation
   12,940.32 : 17,856.18 = 8,690.52 : x
2. Step 2: Convert to fraction form
   12,940.32/17,856.18 = 8,690.52/x
3. Step 3: Cross multiply
   12,940.32x = 17,856.18 × 8,690.52
4. Step 4: Simplify right side
   12,940.32x = 155,179,489.41
5. Step 5: Solve for x
   x = 155,179,489.41/12,940.32
6. Step 6: Final answer
   x = 11,991.94