Finding the Fourth Proportional to 1,399.01, 1,930.43 and 839.36

Step by Step Solution

1. Step 1: Write the proportion equation
   1,399.01 : 1,930.43 = 839.36 : x
2. Step 2: Convert to fraction form
   1,399.01/1,930.43 = 839.36/x
3. Step 3: Cross multiply
   1,399.01x = 1,930.43 × 839.36
4. Step 4: Simplify right side
   1,399.01x = 1,620,325.72
5. Step 5: Solve for x
   x = 1,620,325.72/1,399.01
6. Step 6: Final answer
   x = 1,158.19