Finding the Fourth Proportional to 1,071.50, 1,478.65 and 629.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,071.50 : 1,478.65 = 629.31 : x
2. Step 2: Convert to fraction form
   1,071.50/1,478.65 = 629.31/x
3. Step 3: Cross multiply
   1,071.50x = 1,478.65 × 629.31
4. Step 4: Simplify right side
   1,071.50x = 930,527.66
5. Step 5: Solve for x
   x = 930,527.66/1,071.50
6. Step 6: Final answer
   x = 868.44