Finding the Fourth Proportional to 8,158.12, 12,239.34 and 3,478.38

Step by Step Solution

1. Step 1: Write the proportion equation
   8,158.12 : 12,239.34 = 3,478.38 : x
2. Step 2: Convert to fraction form
   8,158.12/12,239.34 = 3,478.38/x
3. Step 3: Cross multiply
   8,158.12x = 12,239.34 × 3,478.38
4. Step 4: Simplify right side
   8,158.12x = 42,573,016.53
5. Step 5: Solve for x
   x = 42,573,016.53/8,158.12
6. Step 6: Final answer
   x = 5,218.49