Finding the Fourth Proportional to 12,139.20, 16,749.79 and 7,358.18

Step by Step Solution

1. Step 1: Write the proportion equation
   12,139.20 : 16,749.79 = 7,358.18 : x
2. Step 2: Convert to fraction form
   12,139.20/16,749.79 = 7,358.18/x
3. Step 3: Cross multiply
   12,139.20x = 16,749.79 × 7,358.18
4. Step 4: Simplify right side
   12,139.20x = 123,247,867.64
5. Step 5: Solve for x
   x = 123,247,867.64/12,139.20
6. Step 6: Final answer
   x = 10,152.88