Finding the Third Proportional to 6,400 and 10,520

Step by Step Solution

1. Step 1: Write the proportion equation
   6,400 : 10,520 = 10,520 : x
2. Step 2: Convert to fraction form
   6,400/10,520 = 10,520/x
3. Step 3: Cross multiply
   6,400x = 10,520 × 10,520
4. Step 4: Simplify right side
   6,400x = 110,670,400
5. Step 5: Solve for x
   x = 110,670,400/6,400
6. Step 6: Final answer
   x = 17,292.25