Finding the Third Proportional to 78,456 and 172,747.50

Step by Step Solution

1. Step 1: Write the proportion equation
   78,456 : 172,747.50 = 172,747.50 : x
2. Step 2: Convert to fraction form
   78,456/172,747.50 = 172,747.50/x
3. Step 3: Cross multiply
   78,456x = 172,747.50 × 172,747.50
4. Step 4: Simplify right side
   78,456x = 29,841,698,756.25
5. Step 5: Solve for x
   x = 29,841,698,756.25/78,456
6. Step 6: Final answer
   x = 380,362.23