Finding the Third Proportional to 438,858 and 587,209.50

Step by Step Solution

1. Step 1: Write the proportion equation
   438,858 : 587,209.50 = 587,209.50 : x
2. Step 2: Convert to fraction form
   438,858/587,209.50 = 587,209.50/x
3. Step 3: Cross multiply
   438,858x = 587,209.50 × 587,209.50
4. Step 4: Simplify right side
   438,858x = 344,814,996,890.25
5. Step 5: Solve for x
   x = 344,814,996,890.25/438,858
6. Step 6: Final answer
   x = 785,709.72