Finding the Third Proportional to 82,885 and 128,570

Step by Step Solution

1. Step 1: Write the proportion equation
   82,885 : 128,570 = 128,570 : x
2. Step 2: Convert to fraction form
   82,885/128,570 = 128,570/x
3. Step 3: Cross multiply
   82,885x = 128,570 × 128,570
4. Step 4: Simplify right side
   82,885x = 16,530,244,900
5. Step 5: Solve for x
   x = 16,530,244,900/82,885
6. Step 6: Final answer
   x = 199,435.90