Finding the Fourth Proportional to 1,128.75, 1,557.86 and 818.79

Step by Step Solution

1. Step 1: Write the proportion equation
   1,128.75 : 1,557.86 = 818.79 : x
2. Step 2: Convert to fraction form
   1,128.75/1,557.86 = 818.79/x
3. Step 3: Cross multiply
   1,128.75x = 1,557.86 × 818.79
4. Step 4: Simplify right side
   1,128.75x = 1,275,556.10
5. Step 5: Solve for x
   x = 1,275,556.10/1,128.75
6. Step 6: Final answer
   x = 1,130.06