Finding the Third Proportional to 115,318 and 172,978

Step by Step Solution

1. Step 1: Write the proportion equation
   115,318 : 172,978 = 172,978 : x
2. Step 2: Convert to fraction form
   115,318/172,978 = 172,978/x
3. Step 3: Cross multiply
   115,318x = 172,978 × 172,978
4. Step 4: Simplify right side
   115,318x = 29,921,388,484
5. Step 5: Solve for x
   x = 29,921,388,484/115,318
6. Step 6: Final answer
   x = 259,468.50