Finding the Third Proportional to 640,942 and 978,363

Step by Step Solution

1. Step 1: Write the proportion equation
   640,942 : 978,363 = 978,363 : x
2. Step 2: Convert to fraction form
   640,942/978,363 = 978,363/x
3. Step 3: Cross multiply
   640,942x = 978,363 × 978,363
4. Step 4: Simplify right side
   640,942x = 957,194,159,769
5. Step 5: Solve for x
   x = 957,194,159,769/640,942
6. Step 6: Final answer
   x = 1,493,417.75