Finding the Third Proportional to 218,536 and 333,640

Step by Step Solution

1. Step 1: Write the proportion equation
   218,536 : 333,640 = 333,640 : x
2. Step 2: Convert to fraction form
   218,536/333,640 = 333,640/x
3. Step 3: Cross multiply
   218,536x = 333,640 × 333,640
4. Step 4: Simplify right side
   218,536x = 111,315,649,600
5. Step 5: Solve for x
   x = 111,315,649,600/218,536
6. Step 6: Final answer
   x = 509,369.85