Finding the Fourth Proportional to 1,550.29, 2,139.06 and 921.03

Step by Step Solution

1. Step 1: Write the proportion equation
   1,550.29 : 2,139.06 = 921.03 : x
2. Step 2: Convert to fraction form
   1,550.29/2,139.06 = 921.03/x
3. Step 3: Cross multiply
   1,550.29x = 2,139.06 × 921.03
4. Step 4: Simplify right side
   1,550.29x = 1,970,123.13
5. Step 5: Solve for x
   x = 1,970,123.13/1,550.29
6. Step 6: Final answer
   x = 1,270.81