Finding the Third Proportional to 81,631 and 123,678

Step by Step Solution

1. Step 1: Write the proportion equation
   81,631 : 123,678 = 123,678 : x
2. Step 2: Convert to fraction form
   81,631/123,678 = 123,678/x
3. Step 3: Cross multiply
   81,631x = 123,678 × 123,678
4. Step 4: Simplify right side
   81,631x = 15,296,247,684
5. Step 5: Solve for x
   x = 15,296,247,684/81,631
6. Step 6: Final answer
   x = 187,382.83