Finding the Third Proportional to 142,404 and 311,408

Step by Step Solution

1. Step 1: Write the proportion equation
   142,404 : 311,408 = 311,408 : x
2. Step 2: Convert to fraction form
   142,404/311,408 = 311,408/x
3. Step 3: Cross multiply
   142,404x = 311,408 × 311,408
4. Step 4: Simplify right side
   142,404x = 96,974,942,464
5. Step 5: Solve for x
   x = 96,974,942,464/142,404
6. Step 6: Final answer
   x = 680,984.68