Finding the Third Proportional to 78,688 and 172,928

Step by Step Solution

1. Step 1: Write the proportion equation
   78,688 : 172,928 = 172,928 : x
2. Step 2: Convert to fraction form
   78,688/172,928 = 172,928/x
3. Step 3: Cross multiply
   78,688x = 172,928 × 172,928
4. Step 4: Simplify right side
   78,688x = 29,904,093,184
5. Step 5: Solve for x
   x = 29,904,093,184/78,688
6. Step 6: Final answer
   x = 380,033.72