Finding the Third Proportional to 142,410 and 311,419

Step by Step Solution

1. Step 1: Write the proportion equation
   142,410 : 311,419 = 311,419 : x
2. Step 2: Convert to fraction form
   142,410/311,419 = 311,419/x
3. Step 3: Cross multiply
   142,410x = 311,419 × 311,419
4. Step 4: Simplify right side
   142,410x = 96,981,793,561
5. Step 5: Solve for x
   x = 96,981,793,561/142,410
6. Step 6: Final answer
   x = 681,004.10