Finding the Third Proportional to 10,421 and 21,229

Step by Step Solution

1. Step 1: Write the proportion equation
   10,421 : 21,229 = 21,229 : x
2. Step 2: Convert to fraction form
   10,421/21,229 = 21,229/x
3. Step 3: Cross multiply
   10,421x = 21,229 × 21,229
4. Step 4: Simplify right side
   10,421x = 450,670,441
5. Step 5: Solve for x
   x = 450,670,441/10,421
6. Step 6: Final answer
   x = 43,246.37