Finding the Third Proportional to 321,799.50 and 698,953.50

Step by Step Solution

1. Step 1: Write the proportion equation
   321,799.50 : 698,953.50 = 698,953.50 : x
2. Step 2: Convert to fraction form
   321,799.50/698,953.50 = 698,953.50/x
3. Step 3: Cross multiply
   321,799.50x = 698,953.50 × 698,953.50
4. Step 4: Simplify right side
   321,799.50x = 488,535,995,162.25
5. Step 5: Solve for x
   x = 488,535,995,162.25/321,799.50
6. Step 6: Final answer
   x = 1,518,137.83