Finding the Third Proportional to 8,219.81 and 12,880.69

Step by Step Solution

1. Step 1: Write the proportion equation
   8,219.81 : 12,880.69 = 12,880.69 : x
2. Step 2: Convert to fraction form
   8,219.81/12,880.69 = 12,880.69/x
3. Step 3: Cross multiply
   8,219.81x = 12,880.69 × 12,880.69
4. Step 4: Simplify right side
   8,219.81x = 165,912,110.47
5. Step 5: Solve for x
   x = 165,912,110.47/8,219.81
6. Step 6: Final answer
   x = 20,184.42