Finding the Third Proportional to 16,200 and 21,870

Step by Step Solution

1. Step 1: Write the proportion equation
   16,200 : 21,870 = 21,870 : x
2. Step 2: Convert to fraction form
   16,200/21,870 = 21,870/x
3. Step 3: Cross multiply
   16,200x = 21,870 × 21,870
4. Step 4: Simplify right side
   16,200x = 478,296,900
5. Step 5: Solve for x
   x = 478,296,900/16,200
6. Step 6: Final answer
   x = 29,524.50