Finding the Third Proportional to 8,809 and 12,921.50

Step by Step Solution

1. Step 1: Write the proportion equation
   8,809 : 12,921.50 = 12,921.50 : x
2. Step 2: Convert to fraction form
   8,809/12,921.50 = 12,921.50/x
3. Step 3: Cross multiply
   8,809x = 12,921.50 × 12,921.50
4. Step 4: Simplify right side
   8,809x = 166,965,162.25
5. Step 5: Solve for x
   x = 166,965,162.25/8,809
6. Step 6: Final answer
   x = 18,953.93