Finding the Third Proportional to 31,644 and 67,680

Step by Step Solution

1. Step 1: Write the proportion equation
   31,644 : 67,680 = 67,680 : x
2. Step 2: Convert to fraction form
   31,644/67,680 = 67,680/x
3. Step 3: Cross multiply
   31,644x = 67,680 × 67,680
4. Step 4: Simplify right side
   31,644x = 4,580,582,400
5. Step 5: Solve for x
   x = 4,580,582,400/31,644
6. Step 6: Final answer
   x = 144,753.58