Finding the Third Proportional to 143,418 and 315,144

Step by Step Solution

1. Step 1: Write the proportion equation
   143,418 : 315,144 = 315,144 : x
2. Step 2: Convert to fraction form
   143,418/315,144 = 315,144/x
3. Step 3: Cross multiply
   143,418x = 315,144 × 315,144
4. Step 4: Simplify right side
   143,418x = 99,315,740,736
5. Step 5: Solve for x
   x = 99,315,740,736/143,418
6. Step 6: Final answer
   x = 692,491.46