Finding the Fourth Proportional to 9,388.45, 12,955.86 and 5,139.42

Step by Step Solution

1. Step 1: Write the proportion equation
   9,388.45 : 12,955.86 = 5,139.42 : x
2. Step 2: Convert to fraction form
   9,388.45/12,955.86 = 5,139.42/x
3. Step 3: Cross multiply
   9,388.45x = 12,955.86 × 5,139.42
4. Step 4: Simplify right side
   9,388.45x = 66,585,606.00
5. Step 5: Solve for x
   x = 66,585,606.00/9,388.45
6. Step 6: Final answer
   x = 7,092.29