Finding the Third Proportional to 13,128 and 21,000

Step by Step Solution

1. Step 1: Write the proportion equation
   13,128 : 21,000 = 21,000 : x
2. Step 2: Convert to fraction form
   13,128/21,000 = 21,000/x
3. Step 3: Cross multiply
   13,128x = 21,000 × 21,000
4. Step 4: Simplify right side
   13,128x = 441,000,000
5. Step 5: Solve for x
   x = 441,000,000/13,128
6. Step 6: Final answer
   x = 33,592.32