Finding the Third Proportional to 15,648 and 21,456

Step by Step Solution

1. Step 1: Write the proportion equation
   15,648 : 21,456 = 21,456 : x
2. Step 2: Convert to fraction form
   15,648/21,456 = 21,456/x
3. Step 3: Cross multiply
   15,648x = 21,456 × 21,456
4. Step 4: Simplify right side
   15,648x = 460,359,936
5. Step 5: Solve for x
   x = 460,359,936/15,648
6. Step 6: Final answer
   x = 29,419.73