Finding the Third Proportional to 309,936 and 656,496

Step by Step Solution

1. Step 1: Write the proportion equation
   309,936 : 656,496 = 656,496 : x
2. Step 2: Convert to fraction form
   309,936/656,496 = 656,496/x
3. Step 3: Cross multiply
   309,936x = 656,496 × 656,496
4. Step 4: Simplify right side
   309,936x = 430,986,998,016
5. Step 5: Solve for x
   x = 430,986,998,016/309,936
6. Step 6: Final answer
   x = 1,390,567.72