Finding the Fourth Proportional to 3,978.65, 5,490.56 and 2,210.28

Step by Step Solution

1. Step 1: Write the proportion equation
   3,978.65 : 5,490.56 = 2,210.28 : x
2. Step 2: Convert to fraction form
   3,978.65/5,490.56 = 2,210.28/x
3. Step 3: Cross multiply
   3,978.65x = 5,490.56 × 2,210.28
4. Step 4: Simplify right side
   3,978.65x = 12,135,680.48
5. Step 5: Solve for x
   x = 12,135,680.48/3,978.65
6. Step 6: Final answer
   x = 3,050.20