Finding the Fourth Proportional to 3,978.48, 5,490.40 and 2,186.00

Step by Step Solution

1. Step 1: Write the proportion equation
   3,978.48 : 5,490.40 = 2,186.00 : x
2. Step 2: Convert to fraction form
   3,978.48/5,490.40 = 2,186.00/x
3. Step 3: Cross multiply
   3,978.48x = 5,490.40 × 2,186.00
4. Step 4: Simplify right side
   3,978.48x = 12,002,013.89
5. Step 5: Solve for x
   x = 12,002,013.89/3,978.48
6. Step 6: Final answer
   x = 3,016.73