Finding the Fourth Proportional to 882.72, 1,218.69 and 685.86

Step by Step Solution

1. Step 1: Write the proportion equation
   882.72 : 1,218.69 = 685.86 : x
2. Step 2: Convert to fraction form
   882.72/1,218.69 = 685.86/x
3. Step 3: Cross multiply
   882.72x = 1,218.69 × 685.86
4. Step 4: Simplify right side
   882.72x = 835,850.72
5. Step 5: Solve for x
   x = 835,850.72/882.72
6. Step 6: Final answer
   x = 946.90