Finding the Third Proportional to 78,963.50 and 172,689

Step by Step Solution

1. Step 1: Write the proportion equation
   78,963.50 : 172,689 = 172,689 : x
2. Step 2: Convert to fraction form
   78,963.50/172,689 = 172,689/x
3. Step 3: Cross multiply
   78,963.50x = 172,689 × 172,689
4. Step 4: Simplify right side
   78,963.50x = 29,821,490,721
5. Step 5: Solve for x
   x = 29,821,490,721/78,963.50
6. Step 6: Final answer
   x = 377,661.71