Finding the Fourth Proportional to 865.98, 1,191.69 and 767.94

Step by Step Solution

1. Step 1: Write the proportion equation
   865.98 : 1,191.69 = 767.94 : x
2. Step 2: Convert to fraction form
   865.98/1,191.69 = 767.94/x
3. Step 3: Cross multiply
   865.98x = 1,191.69 × 767.94
4. Step 4: Simplify right side
   865.98x = 915,146.42
5. Step 5: Solve for x
   x = 915,146.42/865.98
6. Step 6: Final answer
   x = 1,056.78