Finding the Third Proportional to 12,488 and 15,788

Step by Step Solution

1. Step 1: Write the proportion equation
   12,488 : 15,788 = 15,788 : x
2. Step 2: Convert to fraction form
   12,488/15,788 = 15,788/x
3. Step 3: Cross multiply
   12,488x = 15,788 × 15,788
4. Step 4: Simplify right side
   12,488x = 249,260,944
5. Step 5: Solve for x
   x = 249,260,944/12,488
6. Step 6: Final answer
   x = 19,960.04