Finding the Third Proportional to 317,887.50 and 690,450

Step by Step Solution

1. Step 1: Write the proportion equation
   317,887.50 : 690,450 = 690,450 : x
2. Step 2: Convert to fraction form
   317,887.50/690,450 = 690,450/x
3. Step 3: Cross multiply
   317,887.50x = 690,450 × 690,450
4. Step 4: Simplify right side
   317,887.50x = 476,721,202,500
5. Step 5: Solve for x
   x = 476,721,202,500/317,887.50
6. Step 6: Final answer
   x = 1,499,653.82