Finding the Fourth Proportional to 12,803.89, 17,669.45 and 7,139

Step by Step Solution

1. Step 1: Write the proportion equation
   12,803.89 : 17,669.45 = 7,139 : x
2. Step 2: Convert to fraction form
   12,803.89/17,669.45 = 7,139/x
3. Step 3: Cross multiply
   12,803.89x = 17,669.45 × 7,139
4. Step 4: Simplify right side
   12,803.89x = 126,142,203.55
5. Step 5: Solve for x
   x = 126,142,203.55/12,803.89
6. Step 6: Final answer
   x = 9,851.87