Finding the Third Proportional to 142,138 and 309,316

Step by Step Solution

1. Step 1: Write the proportion equation
   142,138 : 309,316 = 309,316 : x
2. Step 2: Convert to fraction form
   142,138/309,316 = 309,316/x
3. Step 3: Cross multiply
   142,138x = 309,316 × 309,316
4. Step 4: Simplify right side
   142,138x = 95,676,387,856
5. Step 5: Solve for x
   x = 95,676,387,856/142,138
6. Step 6: Final answer
   x = 673,123.22