Finding the Third Proportional to 298,215 and 621,578

Step by Step Solution

1. Step 1: Write the proportion equation
   298,215 : 621,578 = 621,578 : x
2. Step 2: Convert to fraction form
   298,215/621,578 = 621,578/x
3. Step 3: Cross multiply
   298,215x = 621,578 × 621,578
4. Step 4: Simplify right side
   298,215x = 386,359,210,084
5. Step 5: Solve for x
   x = 386,359,210,084/298,215
6. Step 6: Final answer
   x = 1,295,572.69