Finding the Third Proportional to 9,218 and 13,139

Step by Step Solution

1. Step 1: Write the proportion equation
   9,218 : 13,139 = 13,139 : x
2. Step 2: Convert to fraction form
   9,218/13,139 = 13,139/x
3. Step 3: Cross multiply
   9,218x = 13,139 × 13,139
4. Step 4: Simplify right side
   9,218x = 172,633,321
5. Step 5: Solve for x
   x = 172,633,321/9,218
6. Step 6: Final answer
   x = 18,727.85