Finding the Fourth Proportional to 12,456.49, 17,189.17 and 7,147.57

Step by Step Solution

1. Step 1: Write the proportion equation
   12,456.49 : 17,189.17 = 7,147.57 : x
2. Step 2: Convert to fraction form
   12,456.49/17,189.17 = 7,147.57/x
3. Step 3: Cross multiply
   12,456.49x = 17,189.17 × 7,147.57
4. Step 4: Simplify right side
   12,456.49x = 122,860,795.82
5. Step 5: Solve for x
   x = 122,860,795.82/12,456.49
6. Step 6: Final answer
   x = 9,863.20