Finding the Third Proportional to 105,540 and 215,386

Step by Step Solution

1. Step 1: Write the proportion equation
   105,540 : 215,386 = 215,386 : x
2. Step 2: Convert to fraction form
   105,540/215,386 = 215,386/x
3. Step 3: Cross multiply
   105,540x = 215,386 × 215,386
4. Step 4: Simplify right side
   105,540x = 46,391,128,996
5. Step 5: Solve for x
   x = 46,391,128,996/105,540
6. Step 6: Final answer
   x = 439,559.68