Finding the Third Proportional to 78,816 and 172,704

Step by Step Solution

1. Step 1: Write the proportion equation
   78,816 : 172,704 = 172,704 : x
2. Step 2: Convert to fraction form
   78,816/172,704 = 172,704/x
3. Step 3: Cross multiply
   78,816x = 172,704 × 172,704
4. Step 4: Simplify right side
   78,816x = 29,826,671,616
5. Step 5: Solve for x
   x = 29,826,671,616/78,816
6. Step 6: Final answer
   x = 378,434.22