Finding the Fourth Proportional to 1,086.12, 1,626.09 and 921.41

Step by Step Solution

1. Step 1: Write the proportion equation
   1,086.12 : 1,626.09 = 921.41 : x
2. Step 2: Convert to fraction form
   1,086.12/1,626.09 = 921.41/x
3. Step 3: Cross multiply
   1,086.12x = 1,626.09 × 921.41
4. Step 4: Simplify right side
   1,086.12x = 1,498,287.46
5. Step 5: Solve for x
   x = 1,498,287.46/1,086.12
6. Step 6: Final answer
   x = 1,379.49