Finding the Third Proportional to 9,309 and 19,909.50

Step by Step Solution

1. Step 1: Write the proportion equation
   9,309 : 19,909.50 = 19,909.50 : x
2. Step 2: Convert to fraction form
   9,309/19,909.50 = 19,909.50/x
3. Step 3: Cross multiply
   9,309x = 19,909.50 × 19,909.50
4. Step 4: Simplify right side
   9,309x = 396,388,190.25
5. Step 5: Solve for x
   x = 396,388,190.25/9,309
6. Step 6: Final answer
   x = 42,581.18