Finding the Fourth Proportional to 1,389.27, 1,917.16 and 768.27

Step by Step Solution

1. Step 1: Write the proportion equation
   1,389.27 : 1,917.16 = 768.27 : x
2. Step 2: Convert to fraction form
   1,389.27/1,917.16 = 768.27/x
3. Step 3: Cross multiply
   1,389.27x = 1,917.16 × 768.27
4. Step 4: Simplify right side
   1,389.27x = 1,472,888.85
5. Step 5: Solve for x
   x = 1,472,888.85/1,389.27
6. Step 6: Final answer
   x = 1,060.19