Finding the Fourth Proportional to 1,443.30, 2,164.91 and 518.91

Step by Step Solution

1. Step 1: Write the proportion equation
   1,443.30 : 2,164.91 = 518.91 : x
2. Step 2: Convert to fraction form
   1,443.30/2,164.91 = 518.91/x
3. Step 3: Cross multiply
   1,443.30x = 2,164.91 × 518.91
4. Step 4: Simplify right side
   1,443.30x = 1,123,390.85
5. Step 5: Solve for x
   x = 1,123,390.85/1,443.30
6. Step 6: Final answer
   x = 778.35