Finding the Third Proportional to 13,872 and 21,216

Step by Step Solution

1. Step 1: Write the proportion equation
   13,872 : 21,216 = 21,216 : x
2. Step 2: Convert to fraction form
   13,872/21,216 = 21,216/x
3. Step 3: Cross multiply
   13,872x = 21,216 × 21,216
4. Step 4: Simplify right side
   13,872x = 450,118,656
5. Step 5: Solve for x
   x = 450,118,656/13,872
6. Step 6: Final answer
   x = 32,448