Finding the Third Proportional to 8,429 and 13,086.50

Step by Step Solution

1. Step 1: Write the proportion equation
   8,429 : 13,086.50 = 13,086.50 : x
2. Step 2: Convert to fraction form
   8,429/13,086.50 = 13,086.50/x
3. Step 3: Cross multiply
   8,429x = 13,086.50 × 13,086.50
4. Step 4: Simplify right side
   8,429x = 171,256,482.25
5. Step 5: Solve for x
   x = 171,256,482.25/8,429
6. Step 6: Final answer
   x = 20,317.53