Finding the Third Proportional to 10,515 and 21,021

Step by Step Solution

1. Step 1: Write the proportion equation
   10,515 : 21,021 = 21,021 : x
2. Step 2: Convert to fraction form
   10,515/21,021 = 21,021/x
3. Step 3: Cross multiply
   10,515x = 21,021 × 21,021
4. Step 4: Simplify right side
   10,515x = 441,882,441
5. Step 5: Solve for x
   x = 441,882,441/10,515
6. Step 6: Final answer
   x = 42,024.01