Finding the Third Proportional to 151,800 and 321,600

Step by Step Solution

1. Step 1: Write the proportion equation
   151,800 : 321,600 = 321,600 : x
2. Step 2: Convert to fraction form
   151,800/321,600 = 321,600/x
3. Step 3: Cross multiply
   151,800x = 321,600 × 321,600
4. Step 4: Simplify right side
   151,800x = 103,426,560,000
5. Step 5: Solve for x
   x = 103,426,560,000/151,800
6. Step 6: Final answer
   x = 681,334.39