Finding the Third Proportional to 15,513.50 and 20,809.50

Step by Step Solution

1. Step 1: Write the proportion equation
   15,513.50 : 20,809.50 = 20,809.50 : x
2. Step 2: Convert to fraction form
   15,513.50/20,809.50 = 20,809.50/x
3. Step 3: Cross multiply
   15,513.50x = 20,809.50 × 20,809.50
4. Step 4: Simplify right side
   15,513.50x = 433,035,290.25
5. Step 5: Solve for x
   x = 433,035,290.25/15,513.50
6. Step 6: Final answer
   x = 27,913.45