Finding the Fourth Proportional to 1,380.42, 1,904.04 and 855.54

Step by Step Solution

1. Step 1: Write the proportion equation
   1,380.42 : 1,904.04 = 855.54 : x
2. Step 2: Convert to fraction form
   1,380.42/1,904.04 = 855.54/x
3. Step 3: Cross multiply
   1,380.42x = 1,904.04 × 855.54
4. Step 4: Simplify right side
   1,380.42x = 1,628,982.38
5. Step 5: Solve for x
   x = 1,628,982.38/1,380.42
6. Step 6: Final answer
   x = 1,180.06