Finding the Third Proportional to 81,978 and 172,776

Step by Step Solution

1. Step 1: Write the proportion equation
   81,978 : 172,776 = 172,776 : x
2. Step 2: Convert to fraction form
   81,978/172,776 = 172,776/x
3. Step 3: Cross multiply
   81,978x = 172,776 × 172,776
4. Step 4: Simplify right side
   81,978x = 29,851,546,176
5. Step 5: Solve for x
   x = 29,851,546,176/81,978
6. Step 6: Final answer
   x = 364,140.94