Finding the Fourth Proportional to 1,238.73, 1,706.54 and 865.05

Step by Step Solution

1. Step 1: Write the proportion equation
   1,238.73 : 1,706.54 = 865.05 : x
2. Step 2: Convert to fraction form
   1,238.73/1,706.54 = 865.05/x
3. Step 3: Cross multiply
   1,238.73x = 1,706.54 × 865.05
4. Step 4: Simplify right side
   1,238.73x = 1,476,238.10
5. Step 5: Solve for x
   x = 1,476,238.10/1,238.73
6. Step 6: Final answer
   x = 1,191.74