Finding the Fourth Proportional to 1,279.72, 1,768.74 and 1,128.04

Step by Step Solution

1. Step 1: Write the proportion equation
   1,279.72 : 1,768.74 = 1,128.04 : x
2. Step 2: Convert to fraction form
   1,279.72/1,768.74 = 1,128.04/x
3. Step 3: Cross multiply
   1,279.72x = 1,768.74 × 1,128.04
4. Step 4: Simplify right side
   1,279.72x = 1,995,209.47
5. Step 5: Solve for x
   x = 1,995,209.47/1,279.72
6. Step 6: Final answer
   x = 1,559.10