Finding the Fourth Proportional to 1,378.72, 1,902.23 and 854.75

Step by Step Solution

1. Step 1: Write the proportion equation
   1,378.72 : 1,902.23 = 854.75 : x
2. Step 2: Convert to fraction form
   1,378.72/1,902.23 = 854.75/x
3. Step 3: Cross multiply
   1,378.72x = 1,902.23 × 854.75
4. Step 4: Simplify right side
   1,378.72x = 1,625,939.59
5. Step 5: Solve for x
   x = 1,625,939.59/1,378.72
6. Step 6: Final answer
   x = 1,179.31