Finding the Third Proportional to 300,118 and 640,412

Step by Step Solution

1. Step 1: Write the proportion equation
   300,118 : 640,412 = 640,412 : x
2. Step 2: Convert to fraction form
   300,118/640,412 = 640,412/x
3. Step 3: Cross multiply
   300,118x = 640,412 × 640,412
4. Step 4: Simplify right side
   300,118x = 410,127,529,744
5. Step 5: Solve for x
   x = 410,127,529,744/300,118
6. Step 6: Final answer
   x = 1,366,554.25