Finding the Third Proportional to 30,800 and 71,978

Step by Step Solution

1. Step 1: Write the proportion equation
   30,800 : 71,978 = 71,978 : x
2. Step 2: Convert to fraction form
   30,800/71,978 = 71,978/x
3. Step 3: Cross multiply
   30,800x = 71,978 × 71,978
4. Step 4: Simplify right side
   30,800x = 5,180,832,484
5. Step 5: Solve for x
   x = 5,180,832,484/30,800
6. Step 6: Final answer
   x = 168,208.85