Finding the Third Proportional to 131,210 and 287,638

Step by Step Solution

1. Step 1: Write the proportion equation
   131,210 : 287,638 = 287,638 : x
2. Step 2: Convert to fraction form
   131,210/287,638 = 287,638/x
3. Step 3: Cross multiply
   131,210x = 287,638 × 287,638
4. Step 4: Simplify right side
   131,210x = 82,735,619,044
5. Step 5: Solve for x
   x = 82,735,619,044/131,210
6. Step 6: Final answer
   x = 630,558.79