Finding the Fourth Proportional to 1,023.21, 1,411.90 and 581.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,023.21 : 1,411.90 = 581.15 : x
2. Step 2: Convert to fraction form
   1,023.21/1,411.90 = 581.15/x
3. Step 3: Cross multiply
   1,023.21x = 1,411.90 × 581.15
4. Step 4: Simplify right side
   1,023.21x = 820,527.76
5. Step 5: Solve for x
   x = 820,527.76/1,023.21
6. Step 6: Final answer
   x = 801.92