Finding the Third Proportional to 10,240 and 17,920

Step by Step Solution

1. Step 1: Write the proportion equation
   10,240 : 17,920 = 17,920 : x
2. Step 2: Convert to fraction form
   10,240/17,920 = 17,920/x
3. Step 3: Cross multiply
   10,240x = 17,920 × 17,920
4. Step 4: Simplify right side
   10,240x = 321,126,400
5. Step 5: Solve for x
   x = 321,126,400/10,240
6. Step 6: Final answer
   x = 31,360