Finding the Fourth Proportional to 1,377.42, 2,063.52 and 855.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,377.42 : 2,063.52 = 855.78 : x
2. Step 2: Convert to fraction form
   1,377.42/2,063.52 = 855.78/x
3. Step 3: Cross multiply
   1,377.42x = 2,063.52 × 855.78
4. Step 4: Simplify right side
   1,377.42x = 1,765,919.15
5. Step 5: Solve for x
   x = 1,765,919.15/1,377.42
6. Step 6: Final answer
   x = 1,282.05