Finding the Third Proportional to 839,218 and 1,290,678

Step by Step Solution

1. Step 1: Write the proportion equation
   839,218 : 1,290,678 = 1,290,678 : x
2. Step 2: Convert to fraction form
   839,218/1,290,678 = 1,290,678/x
3. Step 3: Cross multiply
   839,218x = 1,290,678 × 1,290,678
4. Step 4: Simplify right side
   839,218x = 1,665,849,699,684
5. Step 5: Solve for x
   x = 1,665,849,699,684/839,218
6. Step 6: Final answer
   x = 1,985,002.35