Finding the Third Proportional to 211,198 and 439,870

Step by Step Solution

1. Step 1: Write the proportion equation
   211,198 : 439,870 = 439,870 : x
2. Step 2: Convert to fraction form
   211,198/439,870 = 439,870/x
3. Step 3: Cross multiply
   211,198x = 439,870 × 439,870
4. Step 4: Simplify right side
   211,198x = 193,485,616,900
5. Step 5: Solve for x
   x = 193,485,616,900/211,198
6. Step 6: Final answer
   x = 916,133.76