Finding the Third Proportional to 5,151 and 10,428

Step by Step Solution

1. Step 1: Write the proportion equation
   5,151 : 10,428 = 10,428 : x
2. Step 2: Convert to fraction form
   5,151/10,428 = 10,428/x
3. Step 3: Cross multiply
   5,151x = 10,428 × 10,428
4. Step 4: Simplify right side
   5,151x = 108,743,184
5. Step 5: Solve for x
   x = 108,743,184/5,151
6. Step 6: Final answer
   x = 21,111.08