Finding the Third Proportional to 21,405 and 31,488

Step by Step Solution

1. Step 1: Write the proportion equation
   21,405 : 31,488 = 31,488 : x
2. Step 2: Convert to fraction form
   21,405/31,488 = 31,488/x
3. Step 3: Cross multiply
   21,405x = 31,488 × 31,488
4. Step 4: Simplify right side
   21,405x = 991,494,144
5. Step 5: Solve for x
   x = 991,494,144/21,405
6. Step 6: Final answer
   x = 46,320.68