Finding the Third Proportional to 288,870 and 422,608

Step by Step Solution

1. Step 1: Write the proportion equation
   288,870 : 422,608 = 422,608 : x
2. Step 2: Convert to fraction form
   288,870/422,608 = 422,608/x
3. Step 3: Cross multiply
   288,870x = 422,608 × 422,608
4. Step 4: Simplify right side
   288,870x = 178,597,521,664
5. Step 5: Solve for x
   x = 178,597,521,664/288,870
6. Step 6: Final answer
   x = 618,262.62