Finding the Fourth Proportional to 1,621.89, 2,238.41 and 959.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,621.89 : 2,238.41 = 959.31 : x
2. Step 2: Convert to fraction form
   1,621.89/2,238.41 = 959.31/x
3. Step 3: Cross multiply
   1,621.89x = 2,238.41 × 959.31
4. Step 4: Simplify right side
   1,621.89x = 2,147,324.30
5. Step 5: Solve for x
   x = 2,147,324.30/1,621.89
6. Step 6: Final answer
   x = 1,323.96