Finding the Fourth Proportional to 13,706.38, 18,915.15 and 8,404.12

Step by Step Solution

1. Step 1: Write the proportion equation
   13,706.38 : 18,915.15 = 8,404.12 : x
2. Step 2: Convert to fraction form
   13,706.38/18,915.15 = 8,404.12/x
3. Step 3: Cross multiply
   13,706.38x = 18,915.15 × 8,404.12
4. Step 4: Simplify right side
   13,706.38x = 158,965,190.42
5. Step 5: Solve for x
   x = 158,965,190.42/13,706.38
6. Step 6: Final answer
   x = 11,597.90