Finding the Fourth Proportional to 1,443.72, 2,163.76 and 620.88

Step by Step Solution

1. Step 1: Write the proportion equation
   1,443.72 : 2,163.76 = 620.88 : x
2. Step 2: Convert to fraction form
   1,443.72/2,163.76 = 620.88/x
3. Step 3: Cross multiply
   1,443.72x = 2,163.76 × 620.88
4. Step 4: Simplify right side
   1,443.72x = 1,343,435.31
5. Step 5: Solve for x
   x = 1,343,435.31/1,443.72
6. Step 6: Final answer
   x = 930.54