Finding the Third Proportional to 258,864 and 406,164

Step by Step Solution

1. Step 1: Write the proportion equation
   258,864 : 406,164 = 406,164 : x
2. Step 2: Convert to fraction form
   258,864/406,164 = 406,164/x
3. Step 3: Cross multiply
   258,864x = 406,164 × 406,164
4. Step 4: Simplify right side
   258,864x = 164,969,194,896
5. Step 5: Solve for x
   x = 164,969,194,896/258,864
6. Step 6: Final answer
   x = 637,281.33