Finding the Third Proportional to 117,007 and 128,488

Step by Step Solution

1. Step 1: Write the proportion equation
   117,007 : 128,488 = 128,488 : x
2. Step 2: Convert to fraction form
   117,007/128,488 = 128,488/x
3. Step 3: Cross multiply
   117,007x = 128,488 × 128,488
4. Step 4: Simplify right side
   117,007x = 16,509,166,144
5. Step 5: Solve for x
   x = 16,509,166,144/117,007
6. Step 6: Final answer
   x = 141,095.54