Finding the Third Proportional to 13,870 and 20,823

Step by Step Solution

1. Step 1: Write the proportion equation
   13,870 : 20,823 = 20,823 : x
2. Step 2: Convert to fraction form
   13,870/20,823 = 20,823/x
3. Step 3: Cross multiply
   13,870x = 20,823 × 20,823
4. Step 4: Simplify right side
   13,870x = 433,597,329
5. Step 5: Solve for x
   x = 433,597,329/13,870
6. Step 6: Final answer
   x = 31,261.52