Finding the Fourth Proportional to 2,622.09, 3,931.98 and 1,389.22

Step by Step Solution

1. Step 1: Write the proportion equation
   2,622.09 : 3,931.98 = 1,389.22 : x
2. Step 2: Convert to fraction form
   2,622.09/3,931.98 = 1,389.22/x
3. Step 3: Cross multiply
   2,622.09x = 3,931.98 × 1,389.22
4. Step 4: Simplify right side
   2,622.09x = 5,462,380.64
5. Step 5: Solve for x
   x = 5,462,380.64/2,622.09
6. Step 6: Final answer
   x = 2,083.21