Finding the Third Proportional to 213,446 and 300,315

Step by Step Solution

1. Step 1: Write the proportion equation
   213,446 : 300,315 = 300,315 : x
2. Step 2: Convert to fraction form
   213,446/300,315 = 300,315/x
3. Step 3: Cross multiply
   213,446x = 300,315 × 300,315
4. Step 4: Simplify right side
   213,446x = 90,189,099,225
5. Step 5: Solve for x
   x = 90,189,099,225/213,446
6. Step 6: Final answer
   x = 422,538.25