Finding the Third Proportional to 13,640 and 20,510.50

Step by Step Solution

1. Step 1: Write the proportion equation
   13,640 : 20,510.50 = 20,510.50 : x
2. Step 2: Convert to fraction form
   13,640/20,510.50 = 20,510.50/x
3. Step 3: Cross multiply
   13,640x = 20,510.50 × 20,510.50
4. Step 4: Simplify right side
   13,640x = 420,680,610.25
5. Step 5: Solve for x
   x = 420,680,610.25/13,640
6. Step 6: Final answer
   x = 30,841.69