Finding the Fourth Proportional to 1,556.37, 2,147.78 and 857.74

Step by Step Solution

1. Step 1: Write the proportion equation
   1,556.37 : 2,147.78 = 857.74 : x
2. Step 2: Convert to fraction form
   1,556.37/2,147.78 = 857.74/x
3. Step 3: Cross multiply
   1,556.37x = 2,147.78 × 857.74
4. Step 4: Simplify right side
   1,556.37x = 1,842,236.82
5. Step 5: Solve for x
   x = 1,842,236.82/1,556.37
6. Step 6: Final answer
   x = 1,183.68