Finding the Fourth Proportional to 2,171.22, 3,256.56 and 872.28

Step by Step Solution

1. Step 1: Write the proportion equation
   2,171.22 : 3,256.56 = 872.28 : x
2. Step 2: Convert to fraction form
   2,171.22/3,256.56 = 872.28/x
3. Step 3: Cross multiply
   2,171.22x = 3,256.56 × 872.28
4. Step 4: Simplify right side
   2,171.22x = 2,840,632.16
5. Step 5: Solve for x
   x = 2,840,632.16/2,171.22
6. Step 6: Final answer
   x = 1,308.31