Finding the Third Proportional to 8,478 and 13,185

Step by Step Solution

1. Step 1: Write the proportion equation
   8,478 : 13,185 = 13,185 : x
2. Step 2: Convert to fraction form
   8,478/13,185 = 13,185/x
3. Step 3: Cross multiply
   8,478x = 13,185 × 13,185
4. Step 4: Simplify right side
   8,478x = 173,844,225
5. Step 5: Solve for x
   x = 173,844,225/8,478
6. Step 6: Final answer
   x = 20,505.33