Finding the Third Proportional to 142,872 and 215,605

Step by Step Solution

1. Step 1: Write the proportion equation
   142,872 : 215,605 = 215,605 : x
2. Step 2: Convert to fraction form
   142,872/215,605 = 215,605/x
3. Step 3: Cross multiply
   142,872x = 215,605 × 215,605
4. Step 4: Simplify right side
   142,872x = 46,485,516,025
5. Step 5: Solve for x
   x = 46,485,516,025/142,872
6. Step 6: Final answer
   x = 325,364.77