Finding the Third Proportional to 12,399.75 and 28,721.25

Step by Step Solution

1. Step 1: Write the proportion equation
   12,399.75 : 28,721.25 = 28,721.25 : x
2. Step 2: Convert to fraction form
   12,399.75/28,721.25 = 28,721.25/x
3. Step 3: Cross multiply
   12,399.75x = 28,721.25 × 28,721.25
4. Step 4: Simplify right side
   12,399.75x = 824,910,201.56
5. Step 5: Solve for x
   x = 824,910,201.56/12,399.75
6. Step 6: Final answer
   x = 66,526.36