Finding the Fourth Proportional to 2,868.76, 4,303.55 and 920.31

Step by Step Solution

1. Step 1: Write the proportion equation
   2,868.76 : 4,303.55 = 920.31 : x
2. Step 2: Convert to fraction form
   2,868.76/4,303.55 = 920.31/x
3. Step 3: Cross multiply
   2,868.76x = 4,303.55 × 920.31
4. Step 4: Simplify right side
   2,868.76x = 3,960,573.98
5. Step 5: Solve for x
   x = 3,960,573.98/2,868.76
6. Step 6: Final answer
   x = 1,380.59