Finding the Fourth Proportional to 2,621.34, 3,930.75 and 1,389.33

Step by Step Solution

1. Step 1: Write the proportion equation
   2,621.34 : 3,930.75 = 1,389.33 : x
2. Step 2: Convert to fraction form
   2,621.34/3,930.75 = 1,389.33/x
3. Step 3: Cross multiply
   2,621.34x = 3,930.75 × 1,389.33
4. Step 4: Simplify right side
   2,621.34x = 5,461,108.90
5. Step 5: Solve for x
   x = 5,461,108.90/2,621.34
6. Step 6: Final answer
   x = 2,083.33