Finding the Fourth Proportional to 12,789.86, 17,647.67 and 7,124.47

Step by Step Solution

1. Step 1: Write the proportion equation
   12,789.86 : 17,647.67 = 7,124.47 : x
2. Step 2: Convert to fraction form
   12,789.86/17,647.67 = 7,124.47/x
3. Step 3: Cross multiply
   12,789.86x = 17,647.67 × 7,124.47
4. Step 4: Simplify right side
   12,789.86x = 125,730,215.74
5. Step 5: Solve for x
   x = 125,730,215.74/12,789.86
6. Step 6: Final answer
   x = 9,830.46