Finding the Third Proportional to 249,517.50 and 405,420

Step by Step Solution

1. Step 1: Write the proportion equation
   249,517.50 : 405,420 = 405,420 : x
2. Step 2: Convert to fraction form
   249,517.50/405,420 = 405,420/x
3. Step 3: Cross multiply
   249,517.50x = 405,420 × 405,420
4. Step 4: Simplify right side
   249,517.50x = 164,365,376,400
5. Step 5: Solve for x
   x = 164,365,376,400/249,517.50
6. Step 6: Final answer
   x = 658,732.86