Finding the Third Proportional to 402,990 and 847,520

Step by Step Solution

1. Step 1: Write the proportion equation
   402,990 : 847,520 = 847,520 : x
2. Step 2: Convert to fraction form
   402,990/847,520 = 847,520/x
3. Step 3: Cross multiply
   402,990x = 847,520 × 847,520
4. Step 4: Simplify right side
   402,990x = 718,290,150,400
5. Step 5: Solve for x
   x = 718,290,150,400/402,990
6. Step 6: Final answer
   x = 1,782,401.92