Finding the Third Proportional to 300,242 and 642,436

Step by Step Solution

1. Step 1: Write the proportion equation
   300,242 : 642,436 = 642,436 : x
2. Step 2: Convert to fraction form
   300,242/642,436 = 642,436/x
3. Step 3: Cross multiply
   300,242x = 642,436 × 642,436
4. Step 4: Simplify right side
   300,242x = 412,724,014,096
5. Step 5: Solve for x
   x = 412,724,014,096/300,242
6. Step 6: Final answer
   x = 1,374,637.84