Finding the Third Proportional to 315,328 and 685,088

Step by Step Solution

1. Step 1: Write the proportion equation
   315,328 : 685,088 = 685,088 : x
2. Step 2: Convert to fraction form
   315,328/685,088 = 685,088/x
3. Step 3: Cross multiply
   315,328x = 685,088 × 685,088
4. Step 4: Simplify right side
   315,328x = 469,345,567,744
5. Step 5: Solve for x
   x = 469,345,567,744/315,328
6. Step 6: Final answer
   x = 1,488,436.07