Finding the Third Proportional to 6,840 and 10,260

Step by Step Solution

1. Step 1: Write the proportion equation
   6,840 : 10,260 = 10,260 : x
2. Step 2: Convert to fraction form
   6,840/10,260 = 10,260/x
3. Step 3: Cross multiply
   6,840x = 10,260 × 10,260
4. Step 4: Simplify right side
   6,840x = 105,267,600
5. Step 5: Solve for x
   x = 105,267,600/6,840
6. Step 6: Final answer
   x = 15,390