Finding the Fourth Proportional to 3,989.74, 5,505.94 and 2,221.52

Step by Step Solution

1. Step 1: Write the proportion equation
   3,989.74 : 5,505.94 = 2,221.52 : x
2. Step 2: Convert to fraction form
   3,989.74/5,505.94 = 2,221.52/x
3. Step 3: Cross multiply
   3,989.74x = 5,505.94 × 2,221.52
4. Step 4: Simplify right side
   3,989.74x = 12,231,555.83
5. Step 5: Solve for x
   x = 12,231,555.83/3,989.74
6. Step 6: Final answer
   x = 3,065.75