Finding the Fourth Proportional to 1,320.63, 1,978.37 and 626.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,320.63 : 1,978.37 = 626.31 : x
2. Step 2: Convert to fraction form
   1,320.63/1,978.37 = 626.31/x
3. Step 3: Cross multiply
   1,320.63x = 1,978.37 × 626.31
4. Step 4: Simplify right side
   1,320.63x = 1,239,069.78
5. Step 5: Solve for x
   x = 1,239,069.78/1,320.63
6. Step 6: Final answer
   x = 938.24