Finding the Fourth Proportional to 13,389, 18,477.30 and 8,082.78

Step by Step Solution

1. Step 1: Write the proportion equation
   13,389 : 18,477.30 = 8,082.78 : x
2. Step 2: Convert to fraction form
   13,389/18,477.30 = 8,082.78/x
3. Step 3: Cross multiply
   13,389x = 18,477.30 × 8,082.78
4. Step 4: Simplify right side
   13,389x = 149,347,950.89
5. Step 5: Solve for x
   x = 149,347,950.89/13,389
6. Step 6: Final answer
   x = 11,154.53