Finding the Third Proportional to 142,808 and 311,858

Step by Step Solution

1. Step 1: Write the proportion equation
   142,808 : 311,858 = 311,858 : x
2. Step 2: Convert to fraction form
   142,808/311,858 = 311,858/x
3. Step 3: Cross multiply
   142,808x = 311,858 × 311,858
4. Step 4: Simplify right side
   142,808x = 97,255,412,164
5. Step 5: Solve for x
   x = 97,255,412,164/142,808
6. Step 6: Final answer
   x = 681,022.16