Finding the Third Proportional to 31,381 and 67,690

Step by Step Solution

1. Step 1: Write the proportion equation
   31,381 : 67,690 = 67,690 : x
2. Step 2: Convert to fraction form
   31,381/67,690 = 67,690/x
3. Step 3: Cross multiply
   31,381x = 67,690 × 67,690
4. Step 4: Simplify right side
   31,381x = 4,581,936,100
5. Step 5: Solve for x
   x = 4,581,936,100/31,381
6. Step 6: Final answer
   x = 146,009.88