Finding the Third Proportional to 12,984 and 21,405

Step by Step Solution

1. Step 1: Write the proportion equation
   12,984 : 21,405 = 21,405 : x
2. Step 2: Convert to fraction form
   12,984/21,405 = 21,405/x
3. Step 3: Cross multiply
   12,984x = 21,405 × 21,405
4. Step 4: Simplify right side
   12,984x = 458,174,025
5. Step 5: Solve for x
   x = 458,174,025/12,984
6. Step 6: Final answer
   x = 35,287.59