Finding the Third Proportional to 521,709 and 698,809.50

Step by Step Solution

1. Step 1: Write the proportion equation
   521,709 : 698,809.50 = 698,809.50 : x
2. Step 2: Convert to fraction form
   521,709/698,809.50 = 698,809.50/x
3. Step 3: Cross multiply
   521,709x = 698,809.50 × 698,809.50
4. Step 4: Simplify right side
   521,709x = 488,334,717,290.25
5. Step 5: Solve for x
   x = 488,334,717,290.25/521,709
6. Step 6: Final answer
   x = 936,028.93