Finding the Fourth Proportional to 3,978.99, 5,491.17 and 2,210.85

Step by Step Solution

1. Step 1: Write the proportion equation
   3,978.99 : 5,491.17 = 2,210.85 : x
2. Step 2: Convert to fraction form
   3,978.99/5,491.17 = 2,210.85/x
3. Step 3: Cross multiply
   3,978.99x = 5,491.17 × 2,210.85
4. Step 4: Simplify right side
   3,978.99x = 12,140,153.19
5. Step 5: Solve for x
   x = 12,140,153.19/3,978.99
6. Step 6: Final answer
   x = 3,051.06