Finding the Third Proportional to 640,436 and 1,379,833

Step by Step Solution

1. Step 1: Write the proportion equation
   640,436 : 1,379,833 = 1,379,833 : x
2. Step 2: Convert to fraction form
   640,436/1,379,833 = 1,379,833/x
3. Step 3: Cross multiply
   640,436x = 1,379,833 × 1,379,833
4. Step 4: Simplify right side
   640,436x = 1,903,939,107,889
5. Step 5: Solve for x
   x = 1,903,939,107,889/640,436
6. Step 6: Final answer
   x = 2,972,879.58