Finding the Fourth Proportional to 12,189.83, 18,286.25 and 4,290.48

Step by Step Solution

1. Step 1: Write the proportion equation
   12,189.83 : 18,286.25 = 4,290.48 : x
2. Step 2: Convert to fraction form
   12,189.83/18,286.25 = 4,290.48/x
3. Step 3: Cross multiply
   12,189.83x = 18,286.25 × 4,290.48
4. Step 4: Simplify right side
   12,189.83x = 78,456,768.45
5. Step 5: Solve for x
   x = 78,456,768.45/12,189.83
6. Step 6: Final answer
   x = 6,436.25