Finding the Third Proportional to 9,888 and 21,171

Step by Step Solution

1. Step 1: Write the proportion equation
   9,888 : 21,171 = 21,171 : x
2. Step 2: Convert to fraction form
   9,888/21,171 = 21,171/x
3. Step 3: Cross multiply
   9,888x = 21,171 × 21,171
4. Step 4: Simplify right side
   9,888x = 448,211,241
5. Step 5: Solve for x
   x = 448,211,241/9,888
6. Step 6: Final answer
   x = 45,328.81