Finding the Third Proportional to 257,384 and 404,172

Step by Step Solution

1. Step 1: Write the proportion equation
   257,384 : 404,172 = 404,172 : x
2. Step 2: Convert to fraction form
   257,384/404,172 = 404,172/x
3. Step 3: Cross multiply
   257,384x = 404,172 × 404,172
4. Step 4: Simplify right side
   257,384x = 163,355,005,584
5. Step 5: Solve for x
   x = 163,355,005,584/257,384
6. Step 6: Final answer
   x = 634,674.28