Finding the Third Proportional to 215,212 and 331,890

Step by Step Solution

1. Step 1: Write the proportion equation
   215,212 : 331,890 = 331,890 : x
2. Step 2: Convert to fraction form
   215,212/331,890 = 331,890/x
3. Step 3: Cross multiply
   215,212x = 331,890 × 331,890
4. Step 4: Simplify right side
   215,212x = 110,150,972,100
5. Step 5: Solve for x
   x = 110,150,972,100/215,212
6. Step 6: Final answer
   x = 511,825.42