Finding the Fourth Proportional to 3,978.58, 5,490.63 and 2,210.20

Step by Step Solution

1. Step 1: Write the proportion equation
   3,978.58 : 5,490.63 = 2,210.20 : x
2. Step 2: Convert to fraction form
   3,978.58/5,490.63 = 2,210.20/x
3. Step 3: Cross multiply
   3,978.58x = 5,490.63 × 2,210.20
4. Step 4: Simplify right side
   3,978.58x = 12,135,390.43
5. Step 5: Solve for x
   x = 12,135,390.43/3,978.58
6. Step 6: Final answer
   x = 3,050.18