Finding the Third Proportional to 131,518 and 287,642

Step by Step Solution

1. Step 1: Write the proportion equation
   131,518 : 287,642 = 287,642 : x
2. Step 2: Convert to fraction form
   131,518/287,642 = 287,642/x
3. Step 3: Cross multiply
   131,518x = 287,642 × 287,642
4. Step 4: Simplify right side
   131,518x = 82,737,920,164
5. Step 5: Solve for x
   x = 82,737,920,164/131,518
6. Step 6: Final answer
   x = 629,099.59