Finding the Third Proportional to 12,699 and 20,911.50

Step by Step Solution

1. Step 1: Write the proportion equation
   12,699 : 20,911.50 = 20,911.50 : x
2. Step 2: Convert to fraction form
   12,699/20,911.50 = 20,911.50/x
3. Step 3: Cross multiply
   12,699x = 20,911.50 × 20,911.50
4. Step 4: Simplify right side
   12,699x = 437,290,832.25
5. Step 5: Solve for x
   x = 437,290,832.25/12,699
6. Step 6: Final answer
   x = 34,435.06