Finding the Third Proportional to 31,689 and 69,666

Step by Step Solution

1. Step 1: Write the proportion equation
   31,689 : 69,666 = 69,666 : x
2. Step 2: Convert to fraction form
   31,689/69,666 = 69,666/x
3. Step 3: Cross multiply
   31,689x = 69,666 × 69,666
4. Step 4: Simplify right side
   31,689x = 4,853,351,556
5. Step 5: Solve for x
   x = 4,853,351,556/31,689
6. Step 6: Final answer
   x = 153,155.72