Finding the Third Proportional to 324,312 and 690,718.50

Step by Step Solution

1. Step 1: Write the proportion equation
   324,312 : 690,718.50 = 690,718.50 : x
2. Step 2: Convert to fraction form
   324,312/690,718.50 = 690,718.50/x
3. Step 3: Cross multiply
   324,312x = 690,718.50 × 690,718.50
4. Step 4: Simplify right side
   324,312x = 477,092,046,242.25
5. Step 5: Solve for x
   x = 477,092,046,242.25/324,312
6. Step 6: Final answer
   x = 1,471,089.71