Finding the Fourth Proportional to 3,978.06, 5,488.85 and 2,406.12

Step by Step Solution

1. Step 1: Write the proportion equation
   3,978.06 : 5,488.85 = 2,406.12 : x
2. Step 2: Convert to fraction form
   3,978.06/5,488.85 = 2,406.12/x
3. Step 3: Cross multiply
   3,978.06x = 5,488.85 × 2,406.12
4. Step 4: Simplify right side
   3,978.06x = 13,206,819.73
5. Step 5: Solve for x
   x = 13,206,819.73/3,978.06
6. Step 6: Final answer
   x = 3,319.91