Finding the Third Proportional to 315,854.50 and 690,758

Step by Step Solution

1. Step 1: Write the proportion equation
   315,854.50 : 690,758 = 690,758 : x
2. Step 2: Convert to fraction form
   315,854.50/690,758 = 690,758/x
3. Step 3: Cross multiply
   315,854.50x = 690,758 × 690,758
4. Step 4: Simplify right side
   315,854.50x = 477,146,614,564
5. Step 5: Solve for x
   x = 477,146,614,564/315,854.50
6. Step 6: Final answer
   x = 1,510,653.21