Finding the Fourth Proportional to 3,983.78, 5,497.72 and 2,215.50

Step by Step Solution

1. Step 1: Write the proportion equation
   3,983.78 : 5,497.72 = 2,215.50 : x
2. Step 2: Convert to fraction form
   3,983.78/5,497.72 = 2,215.50/x
3. Step 3: Cross multiply
   3,983.78x = 5,497.72 × 2,215.50
4. Step 4: Simplify right side
   3,983.78x = 12,180,198.66
5. Step 5: Solve for x
   x = 12,180,198.66/3,983.78
6. Step 6: Final answer
   x = 3,057.45