Finding the Third Proportional to 12,720 and 18,502.50

Step by Step Solution

1. Step 1: Write the proportion equation
   12,720 : 18,502.50 = 18,502.50 : x
2. Step 2: Convert to fraction form
   12,720/18,502.50 = 18,502.50/x
3. Step 3: Cross multiply
   12,720x = 18,502.50 × 18,502.50
4. Step 4: Simplify right side
   12,720x = 342,342,506.25
5. Step 5: Solve for x
   x = 342,342,506.25/12,720
6. Step 6: Final answer
   x = 26,913.72