Finding the Third Proportional to 309,870 and 656,946

Step by Step Solution

1. Step 1: Write the proportion equation
   309,870 : 656,946 = 656,946 : x
2. Step 2: Convert to fraction form
   309,870/656,946 = 656,946/x
3. Step 3: Cross multiply
   309,870x = 656,946 × 656,946
4. Step 4: Simplify right side
   309,870x = 431,578,046,916
5. Step 5: Solve for x
   x = 431,578,046,916/309,870
6. Step 6: Final answer
   x = 1,392,771.31