Finding the Fourth Proportional to 1,022.78, 1,411.50 and 629.84

Step by Step Solution

1. Step 1: Write the proportion equation
   1,022.78 : 1,411.50 = 629.84 : x
2. Step 2: Convert to fraction form
   1,022.78/1,411.50 = 629.84/x
3. Step 3: Cross multiply
   1,022.78x = 1,411.50 × 629.84
4. Step 4: Simplify right side
   1,022.78x = 889,019.16
5. Step 5: Solve for x
   x = 889,019.16/1,022.78
6. Step 6: Final answer
   x = 869.22