Finding the Third Proportional to 9,689 and 19,788

Step by Step Solution

1. Step 1: Write the proportion equation
   9,689 : 19,788 = 19,788 : x
2. Step 2: Convert to fraction form
   9,689/19,788 = 19,788/x
3. Step 3: Cross multiply
   9,689x = 19,788 × 19,788
4. Step 4: Simplify right side
   9,689x = 391,564,944
5. Step 5: Solve for x
   x = 391,564,944/9,689
6. Step 6: Final answer
   x = 40,413.35