Finding the Third Proportional to 150,612 and 321,240

Step by Step Solution

1. Step 1: Write the proportion equation
   150,612 : 321,240 = 321,240 : x
2. Step 2: Convert to fraction form
   150,612/321,240 = 321,240/x
3. Step 3: Cross multiply
   150,612x = 321,240 × 321,240
4. Step 4: Simplify right side
   150,612x = 103,195,137,600
5. Step 5: Solve for x
   x = 103,195,137,600/150,612
6. Step 6: Final answer
   x = 685,172.08