Finding the Third Proportional to 21,420 and 28,422

Step by Step Solution

1. Step 1: Write the proportion equation
   21,420 : 28,422 = 28,422 : x
2. Step 2: Convert to fraction form
   21,420/28,422 = 28,422/x
3. Step 3: Cross multiply
   21,420x = 28,422 × 28,422
4. Step 4: Simplify right side
   21,420x = 807,810,084
5. Step 5: Solve for x
   x = 807,810,084/21,420
6. Step 6: Final answer
   x = 37,712.89