Finding the Third Proportional to 82,890 and 128,007

Step by Step Solution

1. Step 1: Write the proportion equation
   82,890 : 128,007 = 128,007 : x
2. Step 2: Convert to fraction form
   82,890/128,007 = 128,007/x
3. Step 3: Cross multiply
   82,890x = 128,007 × 128,007
4. Step 4: Simplify right side
   82,890x = 16,385,792,049
5. Step 5: Solve for x
   x = 16,385,792,049/82,890
6. Step 6: Final answer
   x = 197,681.17