Finding the Fourth Proportional to 2,283.30, 3,422.89 and 821.42

Step by Step Solution

1. Step 1: Write the proportion equation
   2,283.30 : 3,422.89 = 821.42 : x
2. Step 2: Convert to fraction form
   2,283.30/3,422.89 = 821.42/x
3. Step 3: Cross multiply
   2,283.30x = 3,422.89 × 821.42
4. Step 4: Simplify right side
   2,283.30x = 2,811,638.86
5. Step 5: Solve for x
   x = 2,811,638.86/2,283.30
6. Step 6: Final answer
   x = 1,231.39