Finding the Fourth Proportional to 2,120.22, 3,179.52 and 821.52

Step by Step Solution

1. Step 1: Write the proportion equation
   2,120.22 : 3,179.52 = 821.52 : x
2. Step 2: Convert to fraction form
   2,120.22/3,179.52 = 821.52/x
3. Step 3: Cross multiply
   2,120.22x = 3,179.52 × 821.52
4. Step 4: Simplify right side
   2,120.22x = 2,612,039.27
5. Step 5: Solve for x
   x = 2,612,039.27/2,120.22
6. Step 6: Final answer
   x = 1,231.97