Finding the Third Proportional to 89,290 and 138,345

Step by Step Solution

1. Step 1: Write the proportion equation
   89,290 : 138,345 = 138,345 : x
2. Step 2: Convert to fraction form
   89,290/138,345 = 138,345/x
3. Step 3: Cross multiply
   89,290x = 138,345 × 138,345
4. Step 4: Simplify right side
   89,290x = 19,139,339,025
5. Step 5: Solve for x
   x = 19,139,339,025/89,290
6. Step 6: Final answer
   x = 214,350.31