Finding the Fourth Proportional to 1,379.39, 1,903.73 and 855.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,379.39 : 1,903.73 = 855.50 : x
2. Step 2: Convert to fraction form
   1,379.39/1,903.73 = 855.50/x
3. Step 3: Cross multiply
   1,379.39x = 1,903.73 × 855.50
4. Step 4: Simplify right side
   1,379.39x = 1,628,627.22
5. Step 5: Solve for x
   x = 1,628,627.22/1,379.39
6. Step 6: Final answer
   x = 1,180.69