Finding the Third Proportional to 12,721.50 and 28,570.50

Step by Step Solution

1. Step 1: Write the proportion equation
   12,721.50 : 28,570.50 = 28,570.50 : x
2. Step 2: Convert to fraction form
   12,721.50/28,570.50 = 28,570.50/x
3. Step 3: Cross multiply
   12,721.50x = 28,570.50 × 28,570.50
4. Step 4: Simplify right side
   12,721.50x = 816,273,470.25
5. Step 5: Solve for x
   x = 816,273,470.25/12,721.50
6. Step 6: Final answer
   x = 64,164.88