Finding the Fourth Proportional to 2,216.55, 3,058.83 and 1,221.84

Step by Step Solution

1. Step 1: Write the proportion equation
   2,216.55 : 3,058.83 = 1,221.84 : x
2. Step 2: Convert to fraction form
   2,216.55/3,058.83 = 1,221.84/x
3. Step 3: Cross multiply
   2,216.55x = 3,058.83 × 1,221.84
4. Step 4: Simplify right side
   2,216.55x = 3,737,388.81
5. Step 5: Solve for x
   x = 3,737,388.81/2,216.55
6. Step 6: Final answer
   x = 1,686.13