Finding the Fourth Proportional to 1,376.15, 2,064.42 and 855.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,376.15 : 2,064.42 = 855.72 : x
2. Step 2: Convert to fraction form
   1,376.15/2,064.42 = 855.72/x
3. Step 3: Cross multiply
   1,376.15x = 2,064.42 × 855.72
4. Step 4: Simplify right side
   1,376.15x = 1,766,565.48
5. Step 5: Solve for x
   x = 1,766,565.48/1,376.15
6. Step 6: Final answer
   x = 1,283.71