Finding the Fourth Proportional to 13,381.78, 18,461.04 and 9,405.50

Step by Step Solution

1. Step 1: Write the proportion equation
   13,381.78 : 18,461.04 = 9,405.50 : x
2. Step 2: Convert to fraction form
   13,381.78/18,461.04 = 9,405.50/x
3. Step 3: Cross multiply
   13,381.78x = 18,461.04 × 9,405.50
4. Step 4: Simplify right side
   13,381.78x = 173,635,311.72
5. Step 5: Solve for x
   x = 173,635,311.72/13,381.78
6. Step 6: Final answer
   x = 12,975.50