Finding the Fourth Proportional to 1,020.72, 1,408.76 and 627.96

Step by Step Solution

1. Step 1: Write the proportion equation
   1,020.72 : 1,408.76 = 627.96 : x
2. Step 2: Convert to fraction form
   1,020.72/1,408.76 = 627.96/x
3. Step 3: Cross multiply
   1,020.72x = 1,408.76 × 627.96
4. Step 4: Simplify right side
   1,020.72x = 884,644.93
5. Step 5: Solve for x
   x = 884,644.93/1,020.72
6. Step 6: Final answer
   x = 866.69