Finding the Third Proportional to 11,708 and 15,870

Step by Step Solution

1. Step 1: Write the proportion equation
   11,708 : 15,870 = 15,870 : x
2. Step 2: Convert to fraction form
   11,708/15,870 = 15,870/x
3. Step 3: Cross multiply
   11,708x = 15,870 × 15,870
4. Step 4: Simplify right side
   11,708x = 251,856,900
5. Step 5: Solve for x
   x = 251,856,900/11,708
6. Step 6: Final answer
   x = 21,511.52