Finding the Fourth Proportional to 2,215.44, 3,322.56 and 828.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,215.44 : 3,322.56 = 828.72 : x
2. Step 2: Convert to fraction form
   2,215.44/3,322.56 = 828.72/x
3. Step 3: Cross multiply
   2,215.44x = 3,322.56 × 828.72
4. Step 4: Simplify right side
   2,215.44x = 2,753,471.92
5. Step 5: Solve for x
   x = 2,753,471.92/2,215.44
6. Step 6: Final answer
   x = 1,242.86