Finding the Third Proportional to 144,264 and 315,078

Step by Step Solution

1. Step 1: Write the proportion equation
   144,264 : 315,078 = 315,078 : x
2. Step 2: Convert to fraction form
   144,264/315,078 = 315,078/x
3. Step 3: Cross multiply
   144,264x = 315,078 × 315,078
4. Step 4: Simplify right side
   144,264x = 99,274,146,084
5. Step 5: Solve for x
   x = 99,274,146,084/144,264
6. Step 6: Final answer
   x = 688,142.20