Finding the Third Proportional to 142,028 and 309,479

Step by Step Solution

1. Step 1: Write the proportion equation
   142,028 : 309,479 = 309,479 : x
2. Step 2: Convert to fraction form
   142,028/309,479 = 309,479/x
3. Step 3: Cross multiply
   142,028x = 309,479 × 309,479
4. Step 4: Simplify right side
   142,028x = 95,777,251,441
5. Step 5: Solve for x
   x = 95,777,251,441/142,028
6. Step 6: Final answer
   x = 674,354.71