Finding the Third Proportional to 20,809 and 31,912

Step by Step Solution

1. Step 1: Write the proportion equation
   20,809 : 31,912 = 31,912 : x
2. Step 2: Convert to fraction form
   20,809/31,912 = 31,912/x
3. Step 3: Cross multiply
   20,809x = 31,912 × 31,912
4. Step 4: Simplify right side
   20,809x = 1,018,375,744
5. Step 5: Solve for x
   x = 1,018,375,744/20,809
6. Step 6: Final answer
   x = 48,939.20