Finding the Third Proportional to 7,800 and 12,812

Step by Step Solution

1. Step 1: Write the proportion equation
   7,800 : 12,812 = 12,812 : x
2. Step 2: Convert to fraction form
   7,800/12,812 = 12,812/x
3. Step 3: Cross multiply
   7,800x = 12,812 × 12,812
4. Step 4: Simplify right side
   7,800x = 164,147,344
5. Step 5: Solve for x
   x = 164,147,344/7,800
6. Step 6: Final answer
   x = 21,044.53