Finding the Third Proportional to 142,865 and 311,128

Step by Step Solution

1. Step 1: Write the proportion equation
   142,865 : 311,128 = 311,128 : x
2. Step 2: Convert to fraction form
   142,865/311,128 = 311,128/x
3. Step 3: Cross multiply
   142,865x = 311,128 × 311,128
4. Step 4: Simplify right side
   142,865x = 96,800,632,384
5. Step 5: Solve for x
   x = 96,800,632,384/142,865
6. Step 6: Final answer
   x = 677,567.16