Finding the Third Proportional to 143,394 and 315,099

Step by Step Solution

1. Step 1: Write the proportion equation
   143,394 : 315,099 = 315,099 : x
2. Step 2: Convert to fraction form
   143,394/315,099 = 315,099/x
3. Step 3: Cross multiply
   143,394x = 315,099 × 315,099
4. Step 4: Simplify right side
   143,394x = 99,287,379,801
5. Step 5: Solve for x
   x = 99,287,379,801/143,394
6. Step 6: Final answer
   x = 692,409.58