Finding the Third Proportional to 5,218.50 and 8,081.63

Step by Step Solution

1. Step 1: Write the proportion equation
   5,218.50 : 8,081.63 = 8,081.63 : x
2. Step 2: Convert to fraction form
   5,218.50/8,081.63 = 8,081.63/x
3. Step 3: Cross multiply
   5,218.50x = 8,081.63 × 8,081.63
4. Step 4: Simplify right side
   5,218.50x = 65,312,662.64
5. Step 5: Solve for x
   x = 65,312,662.64/5,218.50
6. Step 6: Final answer
   x = 12,515.60