Finding the Third Proportional to 213,648 and 309,456

Step by Step Solution

1. Step 1: Write the proportion equation
   213,648 : 309,456 = 309,456 : x
2. Step 2: Convert to fraction form
   213,648/309,456 = 309,456/x
3. Step 3: Cross multiply
   213,648x = 309,456 × 309,456
4. Step 4: Simplify right side
   213,648x = 95,763,015,936
5. Step 5: Solve for x
   x = 95,763,015,936/213,648
6. Step 6: Final answer
   x = 448,228.00