Finding the Fourth Proportional to 2,216.25, 3,058.41 and 1,221.55

Step by Step Solution

1. Step 1: Write the proportion equation
   2,216.25 : 3,058.41 = 1,221.55 : x
2. Step 2: Convert to fraction form
   2,216.25/3,058.41 = 1,221.55/x
3. Step 3: Cross multiply
   2,216.25x = 3,058.41 × 1,221.55
4. Step 4: Simplify right side
   2,216.25x = 3,735,997.67
5. Step 5: Solve for x
   x = 3,735,997.67/2,216.25
6. Step 6: Final answer
   x = 1,685.73