Finding the Fourth Proportional to 1,009.38, 1,393.25 and 631.47

Step by Step Solution

1. Step 1: Write the proportion equation
   1,009.38 : 1,393.25 = 631.47 : x
2. Step 2: Convert to fraction form
   1,009.38/1,393.25 = 631.47/x
3. Step 3: Cross multiply
   1,009.38x = 1,393.25 × 631.47
4. Step 4: Simplify right side
   1,009.38x = 879,792.42
5. Step 5: Solve for x
   x = 879,792.42/1,009.38
6. Step 6: Final answer
   x = 871.62