Finding the Fourth Proportional to 2,215.72, 3,324.78 and 918.08

Step by Step Solution

1. Step 1: Write the proportion equation
   2,215.72 : 3,324.78 = 918.08 : x
2. Step 2: Convert to fraction form
   2,215.72/3,324.78 = 918.08/x
3. Step 3: Cross multiply
   2,215.72x = 3,324.78 × 918.08
4. Step 4: Simplify right side
   2,215.72x = 3,052,414.02
5. Step 5: Solve for x
   x = 3,052,414.02/2,215.72
6. Step 6: Final answer
   x = 1,377.62