Finding the Fourth Proportional to 1,016.72, 1,404.24 and 668.96

Step by Step Solution

1. Step 1: Write the proportion equation
   1,016.72 : 1,404.24 = 668.96 : x
2. Step 2: Convert to fraction form
   1,016.72/1,404.24 = 668.96/x
3. Step 3: Cross multiply
   1,016.72x = 1,404.24 × 668.96
4. Step 4: Simplify right side
   1,016.72x = 939,380.39
5. Step 5: Solve for x
   x = 939,380.39/1,016.72
6. Step 6: Final answer
   x = 923.93