Finding the Third Proportional to 20,880 and 42,320

Step by Step Solution

1. Step 1: Write the proportion equation
   20,880 : 42,320 = 42,320 : x
2. Step 2: Convert to fraction form
   20,880/42,320 = 42,320/x
3. Step 3: Cross multiply
   20,880x = 42,320 × 42,320
4. Step 4: Simplify right side
   20,880x = 1,790,982,400
5. Step 5: Solve for x
   x = 1,790,982,400/20,880
6. Step 6: Final answer
   x = 85,775.02