Finding the Third Proportional to 323,136 and 690,259.50

Step by Step Solution

1. Step 1: Write the proportion equation
   323,136 : 690,259.50 = 690,259.50 : x
2. Step 2: Convert to fraction form
   323,136/690,259.50 = 690,259.50/x
3. Step 3: Cross multiply
   323,136x = 690,259.50 × 690,259.50
4. Step 4: Simplify right side
   323,136x = 476,458,177,340.25
5. Step 5: Solve for x
   x = 476,458,177,340.25/323,136
6. Step 6: Final answer
   x = 1,474,481.88