Finding the Fourth Proportional to 2,868.18, 4,302.42 and 920.40

Step by Step Solution

1. Step 1: Write the proportion equation
   2,868.18 : 4,302.42 = 920.40 : x
2. Step 2: Convert to fraction form
   2,868.18/4,302.42 = 920.40/x
3. Step 3: Cross multiply
   2,868.18x = 4,302.42 × 920.40
4. Step 4: Simplify right side
   2,868.18x = 3,959,947.37
5. Step 5: Solve for x
   x = 3,959,947.37/2,868.18
6. Step 6: Final answer
   x = 1,380.65