Finding the Third Proportional to 78,804 and 172,920

Step by Step Solution

1. Step 1: Write the proportion equation
   78,804 : 172,920 = 172,920 : x
2. Step 2: Convert to fraction form
   78,804/172,920 = 172,920/x
3. Step 3: Cross multiply
   78,804x = 172,920 × 172,920
4. Step 4: Simplify right side
   78,804x = 29,901,326,400
5. Step 5: Solve for x
   x = 29,901,326,400/78,804
6. Step 6: Final answer
   x = 379,439.20