Finding the Third Proportional to 401,616 and 621,870

Step by Step Solution

1. Step 1: Write the proportion equation
   401,616 : 621,870 = 621,870 : x
2. Step 2: Convert to fraction form
   401,616/621,870 = 621,870/x
3. Step 3: Cross multiply
   401,616x = 621,870 × 621,870
4. Step 4: Simplify right side
   401,616x = 386,722,296,900
5. Step 5: Solve for x
   x = 386,722,296,900/401,616
6. Step 6: Final answer
   x = 962,915.56