Finding the Third Proportional to 142,136 and 309,312

Step by Step Solution

1. Step 1: Write the proportion equation
   142,136 : 309,312 = 309,312 : x
2. Step 2: Convert to fraction form
   142,136/309,312 = 309,312/x
3. Step 3: Cross multiply
   142,136x = 309,312 × 309,312
4. Step 4: Simplify right side
   142,136x = 95,673,913,344
5. Step 5: Solve for x
   x = 95,673,913,344/142,136
6. Step 6: Final answer
   x = 673,115.28