Finding the Third Proportional to 2,638 and 5,640

Step by Step Solution

1. Step 1: Write the proportion equation
   2,638 : 5,640 = 5,640 : x
2. Step 2: Convert to fraction form
   2,638/5,640 = 5,640/x
3. Step 3: Cross multiply
   2,638x = 5,640 × 5,640
4. Step 4: Simplify right side
   2,638x = 31,809,600
5. Step 5: Solve for x
   x = 31,809,600/2,638
6. Step 6: Final answer
   x = 12,058.23