Finding the Third Proportional to 20,079 and 42,420

Step by Step Solution

1. Step 1: Write the proportion equation
   20,079 : 42,420 = 42,420 : x
2. Step 2: Convert to fraction form
   20,079/42,420 = 42,420/x
3. Step 3: Cross multiply
   20,079x = 42,420 × 42,420
4. Step 4: Simplify right side
   20,079x = 1,799,456,400
5. Step 5: Solve for x
   x = 1,799,456,400/20,079
6. Step 6: Final answer
   x = 89,618.83