Finding the Third Proportional to 9,858 and 21,180

Step by Step Solution

1. Step 1: Write the proportion equation
   9,858 : 21,180 = 21,180 : x
2. Step 2: Convert to fraction form
   9,858/21,180 = 21,180/x
3. Step 3: Cross multiply
   9,858x = 21,180 × 21,180
4. Step 4: Simplify right side
   9,858x = 448,592,400
5. Step 5: Solve for x
   x = 448,592,400/9,858
6. Step 6: Final answer
   x = 45,505.42