Finding the Third Proportional to 5,211 and 10,287

Step by Step Solution

1. Step 1: Write the proportion equation
   5,211 : 10,287 = 10,287 : x
2. Step 2: Convert to fraction form
   5,211/10,287 = 10,287/x
3. Step 3: Cross multiply
   5,211x = 10,287 × 10,287
4. Step 4: Simplify right side
   5,211x = 105,822,369
5. Step 5: Solve for x
   x = 105,822,369/5,211
6. Step 6: Final answer
   x = 20,307.50