Finding the Fourth Proportional to 3,105.98, 4,286.60 and 1,780.12

Step by Step Solution

1. Step 1: Write the proportion equation
   3,105.98 : 4,286.60 = 1,780.12 : x
2. Step 2: Convert to fraction form
   3,105.98/4,286.60 = 1,780.12/x
3. Step 3: Cross multiply
   3,105.98x = 4,286.60 × 1,780.12
4. Step 4: Simplify right side
   3,105.98x = 7,630,662.39
5. Step 5: Solve for x
   x = 7,630,662.39/3,105.98
6. Step 6: Final answer
   x = 2,456.76