Finding the Third Proportional to 640,948 and 978,372

Step by Step Solution

1. Step 1: Write the proportion equation
   640,948 : 978,372 = 978,372 : x
2. Step 2: Convert to fraction form
   640,948/978,372 = 978,372/x
3. Step 3: Cross multiply
   640,948x = 978,372 × 978,372
4. Step 4: Simplify right side
   640,948x = 957,211,770,384
5. Step 5: Solve for x
   x = 957,211,770,384/640,948
6. Step 6: Final answer
   x = 1,493,431.25