Finding the Third Proportional to 21,458 and 31,419

Step by Step Solution

1. Step 1: Write the proportion equation
   21,458 : 31,419 = 31,419 : x
2. Step 2: Convert to fraction form
   21,458/31,419 = 31,419/x
3. Step 3: Cross multiply
   21,458x = 31,419 × 31,419
4. Step 4: Simplify right side
   21,458x = 987,153,561
5. Step 5: Solve for x
   x = 987,153,561/21,458
6. Step 6: Final answer
   x = 46,003.99