Finding the Third Proportional to 470,120 and 685,488

Step by Step Solution

1. Step 1: Write the proportion equation
   470,120 : 685,488 = 685,488 : x
2. Step 2: Convert to fraction form
   470,120/685,488 = 685,488/x
3. Step 3: Cross multiply
   470,120x = 685,488 × 685,488
4. Step 4: Simplify right side
   470,120x = 469,893,798,144
5. Step 5: Solve for x
   x = 469,893,798,144/470,120
6. Step 6: Final answer
   x = 999,518.84