Finding the Third Proportional to 31,978 and 68,660

Step by Step Solution

1. Step 1: Write the proportion equation
   31,978 : 68,660 = 68,660 : x
2. Step 2: Convert to fraction form
   31,978/68,660 = 68,660/x
3. Step 3: Cross multiply
   31,978x = 68,660 × 68,660
4. Step 4: Simplify right side
   31,978x = 4,714,195,600
5. Step 5: Solve for x
   x = 4,714,195,600/31,978
6. Step 6: Final answer
   x = 147,419.96