Finding the Third Proportional to 8,421 and 12,492

Step by Step Solution

1. Step 1: Write the proportion equation
   8,421 : 12,492 = 12,492 : x
2. Step 2: Convert to fraction form
   8,421/12,492 = 12,492/x
3. Step 3: Cross multiply
   8,421x = 12,492 × 12,492
4. Step 4: Simplify right side
   8,421x = 156,050,064
5. Step 5: Solve for x
   x = 156,050,064/8,421
6. Step 6: Final answer
   x = 18,531.06