Finding the Third Proportional to 6,921 and 12,870

Step by Step Solution

1. Step 1: Write the proportion equation
   6,921 : 12,870 = 12,870 : x
2. Step 2: Convert to fraction form
   6,921/12,870 = 12,870/x
3. Step 3: Cross multiply
   6,921x = 12,870 × 12,870
4. Step 4: Simplify right side
   6,921x = 165,636,900
5. Step 5: Solve for x
   x = 165,636,900/6,921
6. Step 6: Final answer
   x = 23,932.51