Finding the Fourth Proportional to 16,890.21, 23,307.89 and 9,336.55

Step by Step Solution

1. Step 1: Write the proportion equation
   16,890.21 : 23,307.89 = 9,336.55 : x
2. Step 2: Convert to fraction form
   16,890.21/23,307.89 = 9,336.55/x
3. Step 3: Cross multiply
   16,890.21x = 23,307.89 × 9,336.55
4. Step 4: Simplify right side
   16,890.21x = 217,615,280.38
5. Step 5: Solve for x
   x = 217,615,280.38/16,890.21
6. Step 6: Final answer
   x = 12,884.11