Finding the Fourth Proportional to 1,308.89, 1,963.29 and 443.21

Step by Step Solution

1. Step 1: Write the proportion equation
   1,308.89 : 1,963.29 = 443.21 : x
2. Step 2: Convert to fraction form
   1,308.89/1,963.29 = 443.21/x
3. Step 3: Cross multiply
   1,308.89x = 1,963.29 × 443.21
4. Step 4: Simplify right side
   1,308.89x = 870,139.11
5. Step 5: Solve for x
   x = 870,139.11/1,308.89
6. Step 6: Final answer
   x = 664.79