Finding the Fourth Proportional to 1,071.31, 1,478.21 and 629.05

Step by Step Solution

1. Step 1: Write the proportion equation
   1,071.31 : 1,478.21 = 629.05 : x
2. Step 2: Convert to fraction form
   1,071.31/1,478.21 = 629.05/x
3. Step 3: Cross multiply
   1,071.31x = 1,478.21 × 629.05
4. Step 4: Simplify right side
   1,071.31x = 929,868.00
5. Step 5: Solve for x
   x = 929,868.00/1,071.31
6. Step 6: Final answer
   x = 867.97