Finding the Third Proportional to 200,298 and 406,128

Step by Step Solution

1. Step 1: Write the proportion equation
   200,298 : 406,128 = 406,128 : x
2. Step 2: Convert to fraction form
   200,298/406,128 = 406,128/x
3. Step 3: Cross multiply
   200,298x = 406,128 × 406,128
4. Step 4: Simplify right side
   200,298x = 164,939,952,384
5. Step 5: Solve for x
   x = 164,939,952,384/200,298
6. Step 6: Final answer
   x = 823,472.79