Finding the Fourth Proportional to 8,678.34, 13,018.52 and 3,998.57

Step by Step Solution

1. Step 1: Write the proportion equation
   8,678.34 : 13,018.52 = 3,998.57 : x
2. Step 2: Convert to fraction form
   8,678.34/13,018.52 = 3,998.57/x
3. Step 3: Cross multiply
   8,678.34x = 13,018.52 × 3,998.57
4. Step 4: Simplify right side
   8,678.34x = 52,055,408.42
5. Step 5: Solve for x
   x = 52,055,408.42/8,678.34
6. Step 6: Final answer
   x = 5,998.31