Finding the Third Proportional to 156,673 and 321,640

Step by Step Solution

1. Step 1: Write the proportion equation
   156,673 : 321,640 = 321,640 : x
2. Step 2: Convert to fraction form
   156,673/321,640 = 321,640/x
3. Step 3: Cross multiply
   156,673x = 321,640 × 321,640
4. Step 4: Simplify right side
   156,673x = 103,452,289,600
5. Step 5: Solve for x
   x = 103,452,289,600/156,673
6. Step 6: Final answer
   x = 660,307.07