Finding the Third Proportional to 640,938 and 978,356

Step by Step Solution

1. Step 1: Write the proportion equation
   640,938 : 978,356 = 978,356 : x
2. Step 2: Convert to fraction form
   640,938/978,356 = 978,356/x
3. Step 3: Cross multiply
   640,938x = 978,356 × 978,356
4. Step 4: Simplify right side
   640,938x = 957,180,462,736
5. Step 5: Solve for x
   x = 957,180,462,736/640,938
6. Step 6: Final answer
   x = 1,493,405.70