Finding the Fourth Proportional to 12,839.15, 17,719.34 and 9,257.06

Step by Step Solution

1. Step 1: Write the proportion equation
   12,839.15 : 17,719.34 = 9,257.06 : x
2. Step 2: Convert to fraction form
   12,839.15/17,719.34 = 9,257.06/x
3. Step 3: Cross multiply
   12,839.15x = 17,719.34 × 9,257.06
4. Step 4: Simplify right side
   12,839.15x = 164,028,993.54
5. Step 5: Solve for x
   x = 164,028,993.54/12,839.15
6. Step 6: Final answer
   x = 12,775.69