Finding the Third Proportional to 10,220 and 21,172

Step by Step Solution

1. Step 1: Write the proportion equation
   10,220 : 21,172 = 21,172 : x
2. Step 2: Convert to fraction form
   10,220/21,172 = 21,172/x
3. Step 3: Cross multiply
   10,220x = 21,172 × 21,172
4. Step 4: Simplify right side
   10,220x = 448,253,584
5. Step 5: Solve for x
   x = 448,253,584/10,220
6. Step 6: Final answer
   x = 43,860.43