Finding the Third Proportional to 12,690 and 13,788

Step by Step Solution

1. Step 1: Write the proportion equation
   12,690 : 13,788 = 13,788 : x
2. Step 2: Convert to fraction form
   12,690/13,788 = 13,788/x
3. Step 3: Cross multiply
   12,690x = 13,788 × 13,788
4. Step 4: Simplify right side
   12,690x = 190,108,944
5. Step 5: Solve for x
   x = 190,108,944/12,690
6. Step 6: Final answer
   x = 14,981.00