Finding the Fourth Proportional to 1,006.37, 1,388.18 and 628.47

Step by Step Solution

1. Step 1: Write the proportion equation
   1,006.37 : 1,388.18 = 628.47 : x
2. Step 2: Convert to fraction form
   1,006.37/1,388.18 = 628.47/x
3. Step 3: Cross multiply
   1,006.37x = 1,388.18 × 628.47
4. Step 4: Simplify right side
   1,006.37x = 872,426.34
5. Step 5: Solve for x
   x = 872,426.34/1,006.37
6. Step 6: Final answer
   x = 866.90