Finding the Third Proportional to 12,858 and 18,789

Step by Step Solution

1. Step 1: Write the proportion equation
   12,858 : 18,789 = 18,789 : x
2. Step 2: Convert to fraction form
   12,858/18,789 = 18,789/x
3. Step 3: Cross multiply
   12,858x = 18,789 × 18,789
4. Step 4: Simplify right side
   12,858x = 353,026,521
5. Step 5: Solve for x
   x = 353,026,521/12,858
6. Step 6: Final answer
   x = 27,455.79