Finding the Fourth Proportional to 1,071.42, 1,478.06 and 629.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,071.42 : 1,478.06 = 629.31 : x
2. Step 2: Convert to fraction form
   1,071.42/1,478.06 = 629.31/x
3. Step 3: Cross multiply
   1,071.42x = 1,478.06 × 629.31
4. Step 4: Simplify right side
   1,071.42x = 930,157.94
5. Step 5: Solve for x
   x = 930,157.94/1,071.42
6. Step 6: Final answer
   x = 868.15