Finding the Fourth Proportional to 2,023.30, 2,792.10 and 1,139.30

Step by Step Solution

1. Step 1: Write the proportion equation
   2,023.30 : 2,792.10 = 1,139.30 : x
2. Step 2: Convert to fraction form
   2,023.30/2,792.10 = 1,139.30/x
3. Step 3: Cross multiply
   2,023.30x = 2,792.10 × 1,139.30
4. Step 4: Simplify right side
   2,023.30x = 3,181,039.53
5. Step 5: Solve for x
   x = 3,181,039.53/2,023.30
6. Step 6: Final answer
   x = 1,572.20