Finding the Third Proportional to 8,418 and 13,123

Step by Step Solution

1. Step 1: Write the proportion equation
   8,418 : 13,123 = 13,123 : x
2. Step 2: Convert to fraction form
   8,418/13,123 = 13,123/x
3. Step 3: Cross multiply
   8,418x = 13,123 × 13,123
4. Step 4: Simplify right side
   8,418x = 172,213,129
5. Step 5: Solve for x
   x = 172,213,129/8,418
6. Step 6: Final answer
   x = 20,457.72