Finding the Fourth Proportional to 13,689, 18,890.82 and 7,401.38

Step by Step Solution

1. Step 1: Write the proportion equation
   13,689 : 18,890.82 = 7,401.38 : x
2. Step 2: Convert to fraction form
   13,689/18,890.82 = 7,401.38/x
3. Step 3: Cross multiply
   13,689x = 18,890.82 × 7,401.38
4. Step 4: Simplify right side
   13,689x = 139,818,042.88
5. Step 5: Solve for x
   x = 139,818,042.88/13,689
6. Step 6: Final answer
   x = 10,213.90