Finding the Third Proportional to 388,612 and 840,426

Step by Step Solution

1. Step 1: Write the proportion equation
   388,612 : 840,426 = 840,426 : x
2. Step 2: Convert to fraction form
   388,612/840,426 = 840,426/x
3. Step 3: Cross multiply
   388,612x = 840,426 × 840,426
4. Step 4: Simplify right side
   388,612x = 706,315,861,476
5. Step 5: Solve for x
   x = 706,315,861,476/388,612
6. Step 6: Final answer
   x = 1,817,534.87