Finding the Third Proportional to 9,642 and 12,587

Step by Step Solution

1. Step 1: Write the proportion equation
   9,642 : 12,587 = 12,587 : x
2. Step 2: Convert to fraction form
   9,642/12,587 = 12,587/x
3. Step 3: Cross multiply
   9,642x = 12,587 × 12,587
4. Step 4: Simplify right side
   9,642x = 158,432,569
5. Step 5: Solve for x
   x = 158,432,569/9,642
6. Step 6: Final answer
   x = 16,431.50