Finding the Third Proportional to 111,557 and 217,508

Step by Step Solution

1. Step 1: Write the proportion equation
   111,557 : 217,508 = 217,508 : x
2. Step 2: Convert to fraction form
   111,557/217,508 = 217,508/x
3. Step 3: Cross multiply
   111,557x = 217,508 × 217,508
4. Step 4: Simplify right side
   111,557x = 47,309,730,064
5. Step 5: Solve for x
   x = 47,309,730,064/111,557
6. Step 6: Final answer
   x = 424,085.71