Finding the Third Proportional to 389,928 and 810,492

Step by Step Solution

1. Step 1: Write the proportion equation
   389,928 : 810,492 = 810,492 : x
2. Step 2: Convert to fraction form
   389,928/810,492 = 810,492/x
3. Step 3: Cross multiply
   389,928x = 810,492 × 810,492
4. Step 4: Simplify right side
   389,928x = 656,897,282,064
5. Step 5: Solve for x
   x = 656,897,282,064/389,928
6. Step 6: Final answer
   x = 1,684,663.02