Finding the Third Proportional to 643,812 and 1,385,800

Step by Step Solution

1. Step 1: Write the proportion equation
   643,812 : 1,385,800 = 1,385,800 : x
2. Step 2: Convert to fraction form
   643,812/1,385,800 = 1,385,800/x
3. Step 3: Cross multiply
   643,812x = 1,385,800 × 1,385,800
4. Step 4: Simplify right side
   643,812x = 1,920,441,640,000
5. Step 5: Solve for x
   x = 1,920,441,640,000/643,812
6. Step 6: Final answer
   x = 2,982,923.03