Finding the Fourth Proportional to 940.38, 1,403.72 and 863.34

Step by Step Solution

1. Step 1: Write the proportion equation
   940.38 : 1,403.72 = 863.34 : x
2. Step 2: Convert to fraction form
   940.38/1,403.72 = 863.34/x
3. Step 3: Cross multiply
   940.38x = 1,403.72 × 863.34
4. Step 4: Simplify right side
   940.38x = 1,211,883.31
5. Step 5: Solve for x
   x = 1,211,883.31/940.38
6. Step 6: Final answer
   x = 1,288.72