Finding the Fourth Proportional to 13,057.88, 18,018.06 and 7,680.56

Step by Step Solution

1. Step 1: Write the proportion equation
   13,057.88 : 18,018.06 = 7,680.56 : x
2. Step 2: Convert to fraction form
   13,057.88/18,018.06 = 7,680.56/x
3. Step 3: Cross multiply
   13,057.88x = 18,018.06 × 7,680.56
4. Step 4: Simplify right side
   13,057.88x = 138,388,790.91
5. Step 5: Solve for x
   x = 138,388,790.91/13,057.88
6. Step 6: Final answer
   x = 10,598.11