Finding the Third Proportional to 21,138 and 31,638

Step by Step Solution

1. Step 1: Write the proportion equation
   21,138 : 31,638 = 31,638 : x
2. Step 2: Convert to fraction form
   21,138/31,638 = 31,638/x
3. Step 3: Cross multiply
   21,138x = 31,638 × 31,638
4. Step 4: Simplify right side
   21,138x = 1,000,963,044
5. Step 5: Solve for x
   x = 1,000,963,044/21,138
6. Step 6: Final answer
   x = 47,353.73