Finding the Third Proportional to 11,139 and 12,243

Step by Step Solution

1. Step 1: Write the proportion equation
   11,139 : 12,243 = 12,243 : x
2. Step 2: Convert to fraction form
   11,139/12,243 = 12,243/x
3. Step 3: Cross multiply
   11,139x = 12,243 × 12,243
4. Step 4: Simplify right side
   11,139x = 149,891,049
5. Step 5: Solve for x
   x = 149,891,049/11,139
6. Step 6: Final answer
   x = 13,456.42