Finding the Third Proportional to 30,780 and 67,419

Step by Step Solution

1. Step 1: Write the proportion equation
   30,780 : 67,419 = 67,419 : x
2. Step 2: Convert to fraction form
   30,780/67,419 = 67,419/x
3. Step 3: Cross multiply
   30,780x = 67,419 × 67,419
4. Step 4: Simplify right side
   30,780x = 4,545,321,561
5. Step 5: Solve for x
   x = 4,545,321,561/30,780
6. Step 6: Final answer
   x = 147,671.27