Finding the Fourth Proportional to 9,389.73, 12,957.27 and 5,139.95

Step by Step Solution

1. Step 1: Write the proportion equation
   9,389.73 : 12,957.27 = 5,139.95 : x
2. Step 2: Convert to fraction form
   9,389.73/12,957.27 = 5,139.95/x
3. Step 3: Cross multiply
   9,389.73x = 12,957.27 × 5,139.95
4. Step 4: Simplify right side
   9,389.73x = 66,599,719.94
5. Step 5: Solve for x
   x = 66,599,719.94/9,389.73
6. Step 6: Final answer
   x = 7,092.83