Finding the Third Proportional to 6,510 and 10,821

Step by Step Solution

1. Step 1: Write the proportion equation
   6,510 : 10,821 = 10,821 : x
2. Step 2: Convert to fraction form
   6,510/10,821 = 10,821/x
3. Step 3: Cross multiply
   6,510x = 10,821 × 10,821
4. Step 4: Simplify right side
   6,510x = 117,094,041
5. Step 5: Solve for x
   x = 117,094,041/6,510
6. Step 6: Final answer
   x = 17,986.80