Finding the Third Proportional to 78,684 and 173,172

Step by Step Solution

1. Step 1: Write the proportion equation
   78,684 : 173,172 = 173,172 : x
2. Step 2: Convert to fraction form
   78,684/173,172 = 173,172/x
3. Step 3: Cross multiply
   78,684x = 173,172 × 173,172
4. Step 4: Simplify right side
   78,684x = 29,988,541,584
5. Step 5: Solve for x
   x = 29,988,541,584/78,684
6. Step 6: Final answer
   x = 381,126.30