Finding the Fourth Proportional to 1,392.98, 1,922.50 and 868.74

Step by Step Solution

1. Step 1: Write the proportion equation
   1,392.98 : 1,922.50 = 868.74 : x
2. Step 2: Convert to fraction form
   1,392.98/1,922.50 = 868.74/x
3. Step 3: Cross multiply
   1,392.98x = 1,922.50 × 868.74
4. Step 4: Simplify right side
   1,392.98x = 1,670,152.65
5. Step 5: Solve for x
   x = 1,670,152.65/1,392.98
6. Step 6: Final answer
   x = 1,198.98