Finding the Third Proportional to 78,540 and 172,632

Step by Step Solution

1. Step 1: Write the proportion equation
   78,540 : 172,632 = 172,632 : x
2. Step 2: Convert to fraction form
   78,540/172,632 = 172,632/x
3. Step 3: Cross multiply
   78,540x = 172,632 × 172,632
4. Step 4: Simplify right side
   78,540x = 29,801,807,424
5. Step 5: Solve for x
   x = 29,801,807,424/78,540
6. Step 6: Final answer
   x = 379,447.51