Finding the Third Proportional to 21,168 and 30,240

Step by Step Solution

1. Step 1: Write the proportion equation
   21,168 : 30,240 = 30,240 : x
2. Step 2: Convert to fraction form
   21,168/30,240 = 30,240/x
3. Step 3: Cross multiply
   21,168x = 30,240 × 30,240
4. Step 4: Simplify right side
   21,168x = 914,457,600
5. Step 5: Solve for x
   x = 914,457,600/21,168
6. Step 6: Final answer
   x = 43,200