Finding the Third Proportional to 8,380 and 12,479

Step by Step Solution

1. Step 1: Write the proportion equation
   8,380 : 12,479 = 12,479 : x
2. Step 2: Convert to fraction form
   8,380/12,479 = 12,479/x
3. Step 3: Cross multiply
   8,380x = 12,479 × 12,479
4. Step 4: Simplify right side
   8,380x = 155,725,441
5. Step 5: Solve for x
   x = 155,725,441/8,380
6. Step 6: Final answer
   x = 18,582.99