Finding the Third Proportional to 8,261 and 12,813.50

Step by Step Solution

1. Step 1: Write the proportion equation
   8,261 : 12,813.50 = 12,813.50 : x
2. Step 2: Convert to fraction form
   8,261/12,813.50 = 12,813.50/x
3. Step 3: Cross multiply
   8,261x = 12,813.50 × 12,813.50
4. Step 4: Simplify right side
   8,261x = 164,185,782.25
5. Step 5: Solve for x
   x = 164,185,782.25/8,261
6. Step 6: Final answer
   x = 19,874.81