Finding the Third Proportional to 131,390 and 288,215

Step by Step Solution

1. Step 1: Write the proportion equation
   131,390 : 288,215 = 288,215 : x
2. Step 2: Convert to fraction form
   131,390/288,215 = 288,215/x
3. Step 3: Cross multiply
   131,390x = 288,215 × 288,215
4. Step 4: Simplify right side
   131,390x = 83,067,886,225
5. Step 5: Solve for x
   x = 83,067,886,225/131,390
6. Step 6: Final answer
   x = 632,223.81