Finding the Third Proportional to 150,207.50 and 321,738

Step by Step Solution

1. Step 1: Write the proportion equation
   150,207.50 : 321,738 = 321,738 : x
2. Step 2: Convert to fraction form
   150,207.50/321,738 = 321,738/x
3. Step 3: Cross multiply
   150,207.50x = 321,738 × 321,738
4. Step 4: Simplify right side
   150,207.50x = 103,515,340,644
5. Step 5: Solve for x
   x = 103,515,340,644/150,207.50
6. Step 6: Final answer
   x = 689,148.95