Finding the Fourth Proportional to 2,664.24, 3,996.24 and 815.28

Step by Step Solution

1. Step 1: Write the proportion equation
   2,664.24 : 3,996.24 = 815.28 : x
2. Step 2: Convert to fraction form
   2,664.24/3,996.24 = 815.28/x
3. Step 3: Cross multiply
   2,664.24x = 3,996.24 × 815.28
4. Step 4: Simplify right side
   2,664.24x = 3,258,054.55
5. Step 5: Solve for x
   x = 3,258,054.55/2,664.24
6. Step 6: Final answer
   x = 1,222.88