Finding the Fourth Proportional to 1,397.78, 1,928.91 and 768.33

Step by Step Solution

1. Step 1: Write the proportion equation
   1,397.78 : 1,928.91 = 768.33 : x
2. Step 2: Convert to fraction form
   1,397.78/1,928.91 = 768.33/x
3. Step 3: Cross multiply
   1,397.78x = 1,928.91 × 768.33
4. Step 4: Simplify right side
   1,397.78x = 1,482,042.30
5. Step 5: Solve for x
   x = 1,482,042.30/1,397.78
6. Step 6: Final answer
   x = 1,060.28