Finding the Fourth Proportional to 2,216.52, 3,058.76 and 1,221.89

Step by Step Solution

1. Step 1: Write the proportion equation
   2,216.52 : 3,058.76 = 1,221.89 : x
2. Step 2: Convert to fraction form
   2,216.52/3,058.76 = 1,221.89/x
3. Step 3: Cross multiply
   2,216.52x = 3,058.76 × 1,221.89
4. Step 4: Simplify right side
   2,216.52x = 3,737,446.85
5. Step 5: Solve for x
   x = 3,737,446.85/2,216.52
6. Step 6: Final answer
   x = 1,686.18