Finding the Fourth Proportional to 16,961.59, 23,405.18 and 9,405.91

Step by Step Solution

1. Step 1: Write the proportion equation
   16,961.59 : 23,405.18 = 9,405.91 : x
2. Step 2: Convert to fraction form
   16,961.59/23,405.18 = 9,405.91/x
3. Step 3: Cross multiply
   16,961.59x = 23,405.18 × 9,405.91
4. Step 4: Simplify right side
   16,961.59x = 220,147,016.61
5. Step 5: Solve for x
   x = 220,147,016.61/16,961.59
6. Step 6: Final answer
   x = 12,979.15