Finding the Third Proportional to 10,120 and 20,643

Step by Step Solution

1. Step 1: Write the proportion equation
   10,120 : 20,643 = 20,643 : x
2. Step 2: Convert to fraction form
   10,120/20,643 = 20,643/x
3. Step 3: Cross multiply
   10,120x = 20,643 × 20,643
4. Step 4: Simplify right side
   10,120x = 426,133,449
5. Step 5: Solve for x
   x = 426,133,449/10,120
6. Step 6: Final answer
   x = 42,108.05