Finding the Fourth Proportional to 2,216.05, 3,058.33 and 1,221.51

Step by Step Solution

1. Step 1: Write the proportion equation
   2,216.05 : 3,058.33 = 1,221.51 : x
2. Step 2: Convert to fraction form
   2,216.05/3,058.33 = 1,221.51/x
3. Step 3: Cross multiply
   2,216.05x = 3,058.33 × 1,221.51
4. Step 4: Simplify right side
   2,216.05x = 3,735,774.18
5. Step 5: Solve for x
   x = 3,735,774.18/2,216.05
6. Step 6: Final answer
   x = 1,685.78