Finding the Third Proportional to 7,640 and 12,540

Step by Step Solution

1. Step 1: Write the proportion equation
   7,640 : 12,540 = 12,540 : x
2. Step 2: Convert to fraction form
   7,640/12,540 = 12,540/x
3. Step 3: Cross multiply
   7,640x = 12,540 × 12,540
4. Step 4: Simplify right side
   7,640x = 157,251,600
5. Step 5: Solve for x
   x = 157,251,600/7,640
6. Step 6: Final answer
   x = 20,582.67