Finding the Fourth Proportional to 1,855.56, 2,784.42 and 686.39

Step by Step Solution

1. Step 1: Write the proportion equation
   1,855.56 : 2,784.42 = 686.39 : x
2. Step 2: Convert to fraction form
   1,855.56/2,784.42 = 686.39/x
3. Step 3: Cross multiply
   1,855.56x = 2,784.42 × 686.39
4. Step 4: Simplify right side
   1,855.56x = 1,911,184.12
5. Step 5: Solve for x
   x = 1,911,184.12/1,855.56
6. Step 6: Final answer
   x = 1,029.98