Finding the Fourth Proportional to 1,397.91, 1,929.17 and 768.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,397.91 : 1,929.17 = 768.50 : x
2. Step 2: Convert to fraction form
   1,397.91/1,929.17 = 768.50/x
3. Step 3: Cross multiply
   1,397.91x = 1,929.17 × 768.50
4. Step 4: Simplify right side
   1,397.91x = 1,482,553.66
5. Step 5: Solve for x
   x = 1,482,553.66/1,397.91
6. Step 6: Final answer
   x = 1,060.55