Finding the Third Proportional to 78,840 and 172,296

Step by Step Solution

1. Step 1: Write the proportion equation
   78,840 : 172,296 = 172,296 : x
2. Step 2: Convert to fraction form
   78,840/172,296 = 172,296/x
3. Step 3: Cross multiply
   78,840x = 172,296 × 172,296
4. Step 4: Simplify right side
   78,840x = 29,685,911,616
5. Step 5: Solve for x
   x = 29,685,911,616/78,840
6. Step 6: Final answer
   x = 376,533.63