Finding the Fourth Proportional to 1,555.72, 2,146.88 and 857.10

Step by Step Solution

1. Step 1: Write the proportion equation
   1,555.72 : 2,146.88 = 857.10 : x
2. Step 2: Convert to fraction form
   1,555.72/2,146.88 = 857.10/x
3. Step 3: Cross multiply
   1,555.72x = 2,146.88 × 857.10
4. Step 4: Simplify right side
   1,555.72x = 1,840,090.85
5. Step 5: Solve for x
   x = 1,840,090.85/1,555.72
6. Step 6: Final answer
   x = 1,182.79